Author: Sooemrei

Physics

Physics is the scientific study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines. A scientist who specializes in the field of physics is called a physicist.

Physics is one of the oldest academic disciplines. Over much of the past two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the Scientific Revolution in the 17th century, these natural sciences branched into separate research endeavors. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in these and other academic disciplines such as mathematics and philosophy.

Advances in physics often enable new technologies. For example, advances in the understanding of electromagnetism, solid-state physics, and nuclear physics led directly to the development of technologies that have transformed modern society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.

History

Ancient astronomy

Astronomy is one of the oldest natural sciences. Early civilizations dating before 3000 BCE, such as the Sumerians, ancient Egyptians, and the Indus Valley Civilisation, had a predictive knowledge and a basic awareness of the motions of the Sun, Moon, and stars. The stars and planets, believed to represent gods, were often worshipped. While the explanations for the observed positions of the stars were often unscientific and lacking in evidence, these early observations laid the foundation for later astronomy, as the stars were found to traverse great circles across the sky, which could not explain the positions of the planets.

According to Asger Aaboe, the origins of Western astronomy can be found in Mesopotamia, and all Western efforts in the exact sciences are descended from late Babylonian astronomy. Egyptian astronomers left monuments showing knowledge of the constellations and the motions of the celestial bodies,while Greek poet Homer wrote of various celestial objects in his Iliad and Odyssey; later Greek astronomers provided names, which are still used today, for most constellations visible from the Northern Hemisphere.

Natural philosophy

Natural philosophy has its origins in Greece during the Archaic period (650 BCE – 480 BCE), when pre-Socratic philosophers like Thales rejected non-naturalistic explanations for natural phenomena and proclaimed that every event had a natural cause. They proposed ideas verified by reason and observation, and many of their hypotheses proved successful in experiment; for example, atomism was found to be correct approximately 2000 years after it was proposed by Leucippus and his pupil Democritus.

Aristotle and Hellenistic physics

During the classical period in Greece (6th, 5th and 4th centuries BCE) and in Hellenistic times, natural philosophy developed along many lines of inquiry. Aristotle (Greek: Ἀριστοτέλης, Aristotélēs) (384–322 BCE), a student of Plato, wrote on many subjects, including a substantial treatise on “Physics” – in the 4th century BC. Aristotelian physics was influential for about two millennia. His approach mixed some limited observation with logical deductive arguments, but did not rely on experimental verification of deduced statements. Aristotle’s foundational work in Physics, though very imperfect, formed a framework against which later thinkers further developed the field. His approach is entirely superseded today.

He explained ideas such as motion (and gravity) with the theory of four elements. Aristotle believed that each of the four classical elements (air, fire, water, earth) had its own natural place. Because of their differing densities, each element will revert to its own specific place in the atmosphere. So, because of their weights, fire would be at the top, air underneath fire, then water, then lastly earth. He also stated that when a small amount of one element enters the natural place of another, the less abundant element will automatically go towards its own natural place. For example, if there is a fire on the ground, the flames go up into the air in an attempt to go back into its natural place where it belongs. His laws of motion included: that heavier objects will fall faster, the speed being proportional to the weight and the speed of the object that is falling depends inversely on the density object it is falling through (e.g. density of air). He also stated that, when it comes to violent motion (motion of an object when a force is applied to it by a second object) that the speed that object moves, will only be as fast or strong as the measure of force applied to it. The problem of motion and its causes was studied carefully, leading to the philosophical notion of a “prime mover” as the ultimate source of all motion in the world (Book 8 of his treatise Physics).

Medieval European and Islamic

The Western Roman Empire fell to invaders and internal decay in the fifth century, resulting in a decline in intellectual pursuits in western Europe. By contrast, the Eastern Roman Empire (usually known as the Byzantine Empire) resisted the attacks from invaders and continued to advance various fields of learning, including physics. In the sixth century, John Philoponus challenged the dominant Aristotelian approach to science although much of his work was focused on Christian theology.

In the sixth century, Isidore of Miletus created an important compilation of Archimedes’ works that are copied in the Archimedes Palimpsest. Islamic scholarship inherited Aristotelian physics from the Greeks and during the Islamic Golden Age developed it further, especially placing emphasis on observation and a priori reasoning, developing early forms of the scientific method.

The most notable innovations under Islamic scholarship were in the field of optics and vision, which came from the works of many scientists like Ibn Sahl, Al-Kindi, Ibn al-Haytham, Al-Farisi and Avicenna. The most notable work was The Book of Optics (also known as Kitāb al-Manāẓir), written by Ibn al-Haytham, in which he presented the alternative to the ancient Greek idea about vision. His discussed his experiments with camera obscura, showing that light moved in a straight line; he encouraged readers to reproduce his experiments making him one of the originators of the scientific method.

Scientific Revolution

Physics became a separate science when early modern Europeans used experimental and quantitative methods to discover what are now considered to be the laws of physics.

Major developments in this period include the replacement of the geocentric model of the Solar System with the heliocentric Copernican model, the laws governing the motion of planetary bodies (determined by Johannes Kepler between 1609 and 1619), Galileo’s pioneering work on telescopes and observational astronomy in the 16th and 17th centuries, and Isaac Newton’s discovery and unification of the laws of motion and universal gravitation (that would come to bear his name). Newton, and separately Gottfried Wilhelm Leibniz, developed calculus, the mathematical study of continuous change, and Newton applied it to solve physical problems.

19th century

The discovery of laws in thermodynamics, chemistry, and electromagnetics resulted from research efforts during the Industrial Revolution as energy needs increased. By the end of the 19th century, theories of thermodynamics, mechanics, and electromagnetics matched a wide variety of observations. Taken together these theories became the basis for what would later be called classical physics.

A few experimental results remained inexplicable. Classical electromagnetism presumed a medium, an luminiferous aether to support the propagation of waves, but this medium could not be detected. The intensity of light from hot glowing blackbody objects did not match the predictions of thermodynamics and electromagnetism. The character of electron emission of illuminated metals differed from predictions. These failures, seemingly insignificant in the big picture would upset the physics world in first two decades of the 20th century.

20th century

Modern physics began in the early 20th century with the work of Max Planck in quantum theory and Albert Einstein’s theory of relativity. Both of these theories came about due to inaccuracies in classical mechanics in certain situations. Classical mechanics predicted that the speed of light depends on the motion of the observer, which could not be resolved with the constant speed predicted by Maxwell’s equations of electromagnetism. This discrepancy was corrected by Einstein’s theory of special relativity, which replaced classical mechanics for fast-moving bodies and allowed for a constant speed of light. Black-body radiation provided another problem for classical physics, which was corrected when Planck proposed that the excitation of material oscillators is possible only in discrete steps proportional to their frequency. This, along with the photoelectric effect and a complete theory predicting discrete energy levels of electron orbitals, led to the theory of quantum mechanics improving on classical physics at very small scales.

Quantum mechanics would come to be pioneered by Werner Heisenberg, Erwin Schrödinger and Paul Dirac. From this early work, and work in related fields, the Standard Model of particle physics was derived. Following the discovery of a particle with properties consistent with the Higgs boson at CERN in 2012, all fundamental particles predicted by the standard model, and no others, appear to exist; however, physics beyond the Standard Model, with theories such as supersymmetry, is an active area of research. Areas of mathematics in general are important to this field, such as the study of probabilities and groups.

Core theories

Physics deals with a wide variety of systems, although certain theories are used by all physicists. Each of these theories was experimentally tested numerous times and found to be an adequate approximation of nature. These central theories are important tools for research into more specialized topics, and any physicist, regardless of their specialization, is expected to be literate in them. These include classical mechanics, quantum mechanics, thermodynamics and statistical mechanics, electromagnetism, and special relativity.

Distinction between classical and modern physics

In the first decades of the 20th century physics was revolutionized by the discoveries of quantum mechanics and relativity. The changes were so fundamental that these new concepts became the foundation of “modern physics”, with other topics becoming “classical physics”. The majority of applications of physics are essentially classical.The laws of classical physics accurately describe systems whose important length scales are greater than the atomic scale and whose motions are much slower than the speed of light.Outside of this domain, observations do not match predictions provided by clasical mechaniscs.

Classical theory

Classical physics includes the traditional branches and topics that were recognized and well-developed before the beginning of the 20th century—classical mechanics, thermodynamics, and electromagnetism.Classical mechanics is concerned with bodies acted on by forces and bodies in motion and may be divided into statics (study of the forces on a body or bodies not subject to an acceleration), kinematics (study of motion without regard to its causes), and dynamics (study of motion and the forces that affect it); mechanics may also be divided into solid mechanics and fluid mechanics (known together as continuum mechanics), the latter include such branches as hydrostatics, hydrodynamics and pneumatics. Acoustics is the study of how sound is produced, controlled, transmitted and received. Important modern branches of acoustics include ultrasonics, the study of sound waves of very high frequency beyond the range of human hearing; bioacoustics, the physics of animal calls and hearing, and electroacoustics, the manipulation of audible sound waves using electronics.

Optics, the study of light, is concerned not only with visible light but also with infrared and ultraviolet radiation, which exhibit all of the phenomena of visible light except visibility, e.g., reflection, refraction, interference, diffraction, dispersion, and polarization of light. Heat is a form of energy, the internal energy possessed by the particles of which a substance is composed; thermodynamics deals with the relationships between heat and other forms of energy. Electricity and magnetism have been studied as a single branch of physics since the intimate connection between them was discovered in the early 19th century; an electric current gives rise to a magnetic field, and a changing magnetic field induces an electric current. Electrostatics deals with electric charges at rest, electrodynamics with moving charges, and magnetostatics with magnetic poles at rest.

Modern theory

The discovery of relativity and of quantum mechanics in the first decades of the 20th century transformed the conceptual basis of physics without reducing the practical value of most of the physical theories developed up to that time. Consequently the topics of physics have come to be divided into “classical physics” and “modern physics”, with the latter category including effects related to quantum mechanics and relativity. Classical physics is generally concerned with matter and energy on the normal scale of observation, while much of modern physics is concerned with the behavior of matter and energy under extreme conditions or on a very large or very small scale. For example, atomic and nuclear physics study matter on the smallest scale at which chemical elements can be identified. The physics of elementary particles is on an even smaller scale since it is concerned with the most basic units of matter; this branch of physics is also known as high-energy physics because of the extremely high energies necessary to produce many types of particles in particle accelerators. On this scale, ordinary, commonsensical notions of space, time, matter, and energy are no longer valid.

The two chief theories of modern physics present a different picture of the concepts of space, time, and matter from that presented by classical physics. Classical mechanics approximates nature as continuous, while quantum theory is concerned with the discrete nature of many phenomena at the atomic and subatomic level and with the complementary aspects of particles and waves in the description of such phenomena. The theory of relativity is concerned with the description of phenomena that take place in a frame of reference that is in motion with respect to an observer; the special theory of relativity is concerned with motion in the absence of gravitational fields and the general theory of relativity with motion and its connection with gravitation. Both quantum theory and the theory of relativity find applications in many areas of modern physics.

Fundamental concepts in modern physics include:

Action
Causality
Covariance
Particle
Physical field
Physical interaction
Quantum
Statistical ensemble
Symmetry
Wave

Research

Scientific method

Physicists use the scientific method to test the validity of a physical theory. By using a methodical approach to compare the implications of a theory with the conclusions drawn from its related experiments and observations, physicists are better able to test the validity of a theory in a logical, unbiased, and repeatable way. To that end, experiments are performed and observations are made in order to determine the validity or invalidity of a theory.

A scientific law is a concise verbal or mathematical statement of a relation that expresses a fundamental principle of some theory, such as Newton’s law of universal gravitation.

Theory and experiment

Theorists seek to develop mathematical models that both agree with existing experiments and successfully predict future experimental results, while experimentalists devise and perform experiments to test theoretical predictions and explore new phenomena. Although theory and experiment are developed separately, they strongly affect and depend upon each other. Progress in physics frequently comes about when experimental results defy explanation by existing theories, prompting intense focus on applicable modelling, and when new theories generate experimentally testable predictions, which inspire the development of new experiments (and often related equipment).

Physicists who work at the interplay of theory and experiment are called phenomenologists, who study complex phenomena observed in experiment and work to relate them to a fundamental theory.

Theoretical physics has historically taken inspiration from philosophy; electromagnetism was unified this way Beyond the known universe, the field of theoretical physics also deals with hypothetical issues, such as parallel universes, a multiverse, and higher dimensions. Theorists invoke these ideas in hopes of solving particular problems with existing theories; they then explore the consequences of these ideas and work toward making testable predictions.

Experimental physics expands, and is expanded by, engineering and technology. Experimental physicists who are involved in basic research design and perform experiments with equipment such as particle accelerators and lasers, whereas those involved in applied research often work in industry, developing technologies such as magnetic resonance imaging (MRI) and transistors. Feynman has noted that experimentalists may seek areas that have not been explored well by theorists.

Scope and aims

Physics covers a wide range of phenomena, from elementary particles (such as quarks, neutrinos, and electrons) to the largest superclusters of galaxies. Included in these phenomena are the most basic objects composing all other things. Therefore, physics is sometimes called the “fundamental science”. Physics aims to describe the various phenomena that occur in nature in terms of simpler phenomena. Thus, physics aims to both connect the things observable to humans to root causes, and then connect these causes together.

For example, the ancient Chinese observed that certain rocks (lodestone and magnetite) were attracted to one another by an invisible force. This effect was later called magnetism, which was first rigorously studied in the 17th century. But even before the Chinese discovered magnetism, the ancient Greeks knew of other objects such as amber, that when rubbed with fur would cause a similar invisible attraction between the two This was also first studied rigorously in the 17th century and came to be called electricity. Thus, physics had come to understand two observations of nature in terms of some root cause (electricity and magnetism). However, further work in the 19th century revealed that these two forces were just two different aspects of one force—electromagnetism. This process of “unifying” forces continues today, and electromagnetism and the weak nuclear force are now considered to be two aspects of the electroweak interaction. Physics hopes to find an ultimate reason (theory of everything) for why nature is as it is (see section Current research below for more information).

Current research

In condensed matter physics, an important unsolved theoretical problem is that of high-temperature superconductivity. Many condensed matter experiments are aiming to fabricate workable spintronics and quantum computers.

In particle physics, the first pieces of experimental evidence for physics beyond the Standard Model have begun to appear. Foremost among these are indications that neutrinos have non-zero mass. These experimental results appear to have solved the long-standing solar neutrino problem, and the physics of massive neutrinos remains an area of active theoretical and experimental research. The Large Hadron Collider has already found the Higgs boson, but future research aims to prove or disprove the supersymmetry, which extends the Standard Model of particle physics. Research on the nature of the major mysteries of dark matter and dark energy is also currently ongoing.

Although much progress has been made in high-energy, quantum, and astronomical physics, many everyday phenomena involving complexity, chaos, or turbulence are still poorly understood. Complex problems that seem like they could be solved by a clever application of dynamics and mechanics remain unsolved; examples include the formation of sandpiles, nodes in trickling water, the shape of water droplets, mechanisms of surface tension catastrophes, and self-sorting in shaken heterogeneous collections.

These complex phenomena have received growing attention since the 1970s for several reasons, including the availability of modern mathematical methods and computers, which enabled complex systems to be modeled in new ways. Complex physics has become part of increasingly interdisciplinary research, as exemplified by the study of turbulence in aerodynamics and the observation of pattern formation in biological systems. In the 1932 Annual Review of Fluid Mechanics, Horace Lamb said:

I am an old man now, and when I die and go to heaven there are two matters on which I hope for enlightenment. One is quantum electrodynamics, and the other is the turbulent motion of fluids. And about the former I am rather optimistic.

Branches and fields

Branches of physics include classical mechanics; thermodynamics and statistical mechanics; electromagnetism and photonics; relativity; quantum mechanics, atomic physics, and molecular physics; optics and acoustics; condensed matter physics; high-energy particle physics and nuclear physics; cosmology; and interdisciplinary fields.

Fields

The major fields of physics, along with their subfields and the theories and concepts they employ, are shown in the following table.

Field	Subfields	Major theories	Concepts
Nuclear and particle physics	Nuclear physics, Nuclear astrophysics, Particle physics, Astroparticle physics, Particle physics phenomenology	Standard Model, Quantum field theory, Quantum electrodynamics, Quantum chromodynamics, Electroweak theory, Effective field theory, Lattice field theory, Gauge theory, Supersymmetry, Grand Unified Theory, Superstring theory, M-theory, AdS/CFT correspondence	Fundamental interaction (gravitational, electromagnetic, weak, strong), Elementary particle, Spin, Antimatter, Spontaneous symmetry breaking, Neutrino oscillation, Seesaw mechanism, Brane, String, Quantum gravity, Theory of everything, Vacuum energy
Atomic, molecular, and optical physics	Atomic physics, Molecular physics, Atomic and molecular astrophysics, Chemical physics, Optics, Photonics	Quantum optics, Quantum chemistry, Quantum information science	Photon, Atom, Molecule, Diffraction, Electromagnetic radiation, Laser, Polarization (waves), Spectral line, Casimir effect
Condensed matter physics	Solid-state physics, High-pressure physics, Low-temperature physics, Surface physics, Nanoscale and mesoscopic physics, Polymer physics	BCS theory, Bloch’s theorem, Density functional theory, Fermi gas, Fermi liquid theory, Many-body theory, Statistical mechanics	Phases (gas, liquid, solid), Bose–Einstein condensate, Electrical conduction, Phonon, Magnetism, Self-organization, Semiconductor, superconductor, superfluidity, Spin
Astrophysics	Astronomy, Astrometry, Cosmology, Gravitation physics, High-energy astrophysics, Planetary astrophysics, Plasma physics, Solar physics, Space physics, Stellar astrophysics	Big Bang, Cosmic inflation, General relativity, Newton’s law of universal gravitation, Lambda-CDM model, Magnetohydrodynamics	Black hole, Cosmic background radiation, Cosmic string, Cosmos, Dark energy, Dark matter, Galaxy, Gravity, Gravitational radiation, Gravitational singularity, Planet, Solar System, Star, Supernova, Universe
Applied physics	Accelerator physics, Acoustics, Agrophysics, Atmospheric physics, Biophysics, Chemical physics, Communication physics, Econophysics, Engineering physics, Fluid dynamics, Geophysics, Laser physics, Materials physics, Medical physics, Nanotechnology, Optics, Optoelectronics, Photonics, Photovoltaics, Physical chemistry, Physical oceanography, Physics of computation, Plasma physics, Solid-state devices, Quantum chemistry, Quantum electronics, Quantum information science, Vehicle dynamics

Since the 20th century, the individual fields of physics have become increasingly specialised, and today most physicists work in a single field for their entire careers. “Universalists” such as Einstein (1879–1955) and Lev Landau (1908–1968), who worked in multiple fields of physics, are now very rare.

Contemporary research in physics can be broadly divided into nuclear and particle physics; condensed matter physics; atomic, molecular, and optical physics; astrophysics; and applied physics. Some physics departments also support physics education research and physics outreach.

Nuclear and particle

Particle physics is the study of the elementary constituents of matter and energy and the interactions between them. In addition, particle physicists design and develop the high-energy accelerators, detectors, and computer programsnecessary for this research. The field is also called “high-energy physics” because many elementary particles do not occur naturally but are created only during high-energy collisions of other particles.

Currently, the interactions of elementary particles and fields are described by the Standard Model. The model accounts for the 12 known particles of matter (quarks and leptons) that interact via the strong, weak, and electromagnetic fundamental forces. Dynamics are described in terms of matter particles exchanging gauge bosons (gluons, W and Z bosons, and photons, respectively). The Standard Model also predicts a particle known as the Higgs boson. In July 2012 CERN, the European laboratory for particle physics, announced the detection of a particle consistent with the Higgs boson,an integral part of the Higgs mechanism.

Nuclear physics is the field of physics that studies the constituents and interactions of atomic nuclei. The most commonly known applications of nuclear physics are nuclear power generation and nuclear weapons technology, but the research has provided application in many fields, including those in nuclear medicine and magnetic resonance imaging, ion implantation in materials engineering, and radiocarbon dating in geology and archaeology.

Atomic, molecular, and optical

Atomic, molecular, and optical physics (AMO) is the study of matter—matter and light—matter interactions on the scale of single atoms and molecules. The three areas are grouped together because of their interrelationships, the similarity of methods used, and the commonality of their relevant energy scales. All three areas include both classical, semi-classical and quantum treatments; they can treat their subject from a microscopic view (in contrast to a macroscopic view).

Atomic physics studies the electron shells of atoms. Current research focuses on activities in quantum control, cooling and trapping of atoms and ions,low-temperature collision dynamics and the effects of electron correlation on structure and dynamics. Atomic physics is influenced by the nucleus (see hyperfine splitting), but intra-nuclear phenomena such as fission and fusion are considered part of nuclear physics.

Molecular physics focuses on multi-atomic structures and their internal and external interactions with matter and light. Optical physics is distinct from optics in that it tends to focus not on the control of classical light fields by macroscopic objects but on the fundamental properties of optical fields and their interactions with matter in the microscopic realm.

Condensed matter

Condensed matter physics is the field of physics that deals with the macroscopic physical properties of matter.In particular, it is concerned with the “condensed” phases that appear whenever the number of particles in a system is extremely large and the interactions between them are strong.

The most familiar examples of condensed phases are solids and liquids, which arise from the bonding by way of the electromagnetic force between atoms. More exotic condensed phases include the superfluid and the Bose–Einstein condensate found in certain atomic systems at very low temperature, the superconducting phase exhibited by conduction electrons in certain materials, and the ferromagnetic and antiferromagnetic phases of spins on atomic lattices.

Condensed matter physics is the largest field of contemporary physics. Historically, condensed matter physics grew out of solid-state physics, which is now considered one of its main subfields. The term condensed matter physics was apparently coined by Philip Anderson when he renamed his research group—previously solid-state theory—in 1967. In 1978, the Division of Solid State Physics of the American Physical Society was renamed as the Division of Condensed Matter Physics. Condensed matter physics has a large overlap with chemistry, materials science, nanotechnology and engineering.

Astrophysics

Astrophysics and astronomy are the application of the theories and methods of physics to the study of stellar structure, stellar evolution, the origin of the Solar System, and related problems of cosmology. Because astrophysics is a broad subject, astrophysicists typically apply many disciplines of physics, including mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics.

The discovery by Karl Jansky in 1931 that radio signals were emitted by celestial bodies initiated the science of radio astronomy. Most recently, the frontiers of astronomy have been expanded by space exploration. Perturbations and interference from the Earth’s atmosphere make space-based observations necessary for infrared, ultraviolet, gamma-ray, and X-ray astronomy.

Physical cosmology is the study of the formation and evolution of the universe on its largest scales. Albert Einstein’s theory of relativity plays a central role in all modern cosmological theories. In the early 20th century, Hubble’s discovery that the universe is expanding, as shown by the Hubble diagram, prompted rival explanations known as the steady state universe and the Big Bang.

The Big Bang was confirmed by the success of Big Bang nucleosynthesis and the discovery of the cosmic microwave background in 1964. The Big Bang model rests on two theoretical pillars: Albert Einstein’s general relativity and the cosmological principle. Cosmologists have recently established the ΛCDM model of the evolution of the universe, which includes cosmic inflation, dark energy, and dark matter.

Other aspects

Education

Physics education or physics teaching refers to the education methods currently used to teach physics. The occupation is called physics educator or physics teacher. Physics education research refers to an area of pedagogical research that seeks to improve those methods. Historically, physics has been taught at the high school and college level primarily by the lecture method together with laboratory exercises aimed at verifying concepts taught in the lectures. These concepts are better understood when lectures are accompanied with demonstration, hand-on experiments, and questions that require students to ponder what will happen in an experiment and why. Students who participate in active learning for example with hands-on experiments learn through self-discovery. By trial and error they learn to change their preconceptions about phenomena in physics and discover the underlying concepts. Physics education is part of the broader area of science education.

Careers

A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.Physicists generally are interested in the root or ultimate causes of phenomena, and usually frame their understanding in mathematical terms. They work across a wide range of research fields, spanning all length scales: from sub-atomic and particle physics, through biological physics, to cosmological length scales encompassing the universe as a whole. The field generally includes two types of physicists: experimental physicists who specialize in the observation of natural phenomena and the development and analysis of experiments, and theoretical physicists who specialize in mathematical modeling of physical systems to rationalize, explain and predict natural phenomena.

Physicists can apply their knowledge towards solving practical problems or to developing new technologies (also known as applied physics or engineering physics).

Philosophy

Physics, as with the rest of science, relies on the philosophy of science and its “scientific method” to advance knowledge of the physical world. The scientific method employs a priori and a posteriori reasoning as well as the use of Bayesian inference to measure the validity of a given theory. Study of the philosophical issues surrounding physics, the philosophy of physics, involves issues such as the nature of space and time, determinism, and metaphysical outlooks such as empiricism, naturalism, and realism.

Many physicists have written about the philosophical implications of their work, for instance Laplace, who championed causal determinism,and Erwin Schrödinger, who wrote on quantum mechanics.The mathematical physicist Roger Penrose has been called a Platonist by Stephen Hawking, a view Penrose discusses in his book, The Road to Reality. Hawking referred to himself as an “unashamed reductionist” and took issue with Penrose’s views.

Mathematics provides a compact and exact language used to describe the order in nature. This was noted and advocated by Pythagoras, Plato, Galileo, and Newton. Some theorists, like Hilary Putnam and Penelope Maddy, hold that logical truths, and therefore mathematical reasoning, depend on the empirical world. This is usually combined with the claim that the laws of logic express universal regularities found in the structural features of the world, which may explain the peculiar relation between these fields.

Physics uses mathematics to organise and formulate experimental results. From those results, precise or estimated solutions are obtained, or quantitative results, from which new predictions can be made and experimentally confirmed or negated. The results from physics experiments are numerical data, with their units of measure and estimates of the errors in the measurements. Technologies based on mathematics, like computation have made computational physics an active area of research.

Ontology is a prerequisite for physics, but not for mathematics. It means physics is ultimately concerned with descriptions of the real world, while mathematics is concerned with abstract patterns, even beyond the real world. Thus physics statements are synthetic, while mathematical statements are analytic. Mathematics contains hypotheses, while physics contains theories. Mathematics statements have to be only logically true, while predictions of physics statements must match observed and experimental data.

The distinction is clear-cut, but not always obvious. For example, mathematical physics is the application of mathematics in physics. Its methods are mathematical, but its subject is physical. The problems in this field start with a “mathematical model of a physical situation” (system) and a “mathematical description of a physical law” that will be applied to that system. Every mathematical statement used for solving has a hard-to-find physical meaning. The final mathematical solution has an easier-to-find meaning, because it is what the solver is looking for.

Fundamental vs. applied physics

Physics is a branch of fundamental science (also called basic science). Physics is also called “the fundamental science” because all branches of natural science including chemistry, astronomy, geology, and biology are constrained by laws of physics. Similarly, chemistry is often called the central science because of its role in linking the physical sciences. For example, chemistry studies properties, structures, and reactions of matter (chemistry’s focus on the molecular and atomic scale distinguishes it from physics). Structures are formed because particles exert electrical forces on each other, properties include physical characteristics of given substances, and reactions are bound by laws of physics, like conservation of energy, mass, and charge. Fundamental physics seeks to better explain and understand phenomena in all spheres, without a specific practical application as a goal, other than the deeper insight into the phenomema themselves.

Applied physics is a general term for physics research and development that is intended for a particular use. An applied physics curriculum usually contains a few classes in an applied discipline, like geology or electrical engineering. It usually differs from engineering in that an applied physicist may not be designing something in particular, but rather is using physics or conducting physics research with the aim of developing new technologies or solving a problem.

The approach is similar to that of applied mathematics. Applied physicists use physics in scientific research. For instance, people working on accelerator physics might seek to build better particle detectors for research in theoretical physics.

Physics is used heavily in engineering. For example, statics, a subfield of mechanics, is used in the building of bridges and other static structures. The understanding and use of acoustics results in sound control and better concert halls; similarly, the use of optics creates better optical devices. An understanding of physics makes for more realistic flight simulators, video games, and movies, and is often critical in forensic investigations.

With the standard consensus that the laws of physics are universal and do not change with time, physics can be used to study things that would ordinarily be mired in uncertainty. For example, in the study of the origin of the Earth, a physicist can reasonably model Earth’s mass, temperature, and rate of rotation, as a function of time allowing the extrapolation forward or backward in time and so predict future or prior events. It also allows for simulations in engineering that speed up the development of a new technology.

There is also considerable interdisciplinarity, so many other important fields are influenced by physics (e.g., the fields of econophysics and sociophysics).

March 24, 2025

Motion

In physics, motion is when an object changes its position with respect to a reference point in a given time. Motion is mathematically described in terms of displacement, distance, velocity, acceleration, speed, and frame of reference to an observer, measuring the change in position of the body relative to that frame with a change in time. The branch of physics describing the motion of objects without reference to their cause is called kinematics, while the branch studying forces and their effect on motion is called dynamics.

If an object is not in motion relative to a given frame of reference, it is said to be at rest, motionless, immobile, stationary, or to have a constant or time-invariant position with reference to its surroundings. Modern physics holds that, as there is no absolute frame of reference, Isaac Newton’s concept of absolute motion cannot be determined. Everything in the universe can be considered to be in motion.

Motion applies to various physical systems: objects, bodies, matter particles, matter fields, radiation, radiation fields, radiation particles, curvature, and space-time. One can also speak of the motion of images, shapes, and boundaries. In general, the term motion signifies a continuous change in the position or configuration of a physical system in space. For example, one can talk about the motion of a wave or the motion of a quantum particle, where the configuration consists of the probabilities of the wave or particle occupying specific positions.

Equations of motion

In physics, equations of motion are equations that describe the behavior of a physical system in terms of its motion as a function of time. More specifically, the equations of motion describe the behavior of a physical system as a set of mathematical functions in terms of dynamic variables. These variables are usually spatial coordinates and time, but may include momentum components. The most general choice are generalized coordinates which can be any convenient variables characteristic of the physical system. The functions are defined in a Euclidean space in classical mechanics, but are replaced by curved spaces in relativity. If the dynamics of a system is known, the equations are the solutions for the differential equations describing the motion of the dynamics.

Laws of motion

In physics, the motion of massive bodies is described through two related sets of laws of mechanics. Classical mechanics for super atomic (larger than an atom) objects (such as cars, projectiles, planets, cells, and humans) and quantum mechanics for atomic and sub-atomic objects (such as helium, protons, and electrons). Historically, Newton and Euler formulated three laws of classical mechanics:

Classical mechanics

Classical mechanics is used for describing the motion of macroscopic objects moving at speeds significantly slower than the speed of light, from projectiles to parts of machinery, as well as astronomical objects, such as spacecraft, planets, stars, and galaxies. It produces very accurate results within these domains and is one of the oldest and largest scientific descriptions in science, engineering, and technology.

Classical mechanics is fundamentally based on Newton’s laws of motion. These laws describe the relationship between the forces acting on a body and the motion of that body. They were first compiled by Sir Isaac Newton in his work Philosophiæ Naturalis Principia Mathematica, which was first published on July 5, 1687. Newton’s three laws are:

A body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force. (This is known as the law of inertia.)
Force (F→ ${\vec {F}}$ ) is equal to the change in momentum per change in time (Δmv→Δt ${\frac {\Delta m{\vec {v}}}{\Delta t}}$ ). For a constant mass, force equals mass times acceleration (F→=ma→ ${\vec {F}}=m{\vec {a}}$ ).
For every action, there is an equal and opposite reaction. (In other words, whenever one body exerts a force F→ ${\vec {F}}$ onto a second body, (in some cases, which is standing still) the second body exerts the force −F→ $-{\vec {F}}$ back onto the first body. F→ ${\vec {F}}$ and −F→ $-{\vec {F}}$ are equal in magnitude and opposite in direction. So, the body that exerts F→ ${\vec {F}}$ will be pushed backward.)

Newton’s three laws of motion were the first to accurately provide a mathematical model for understanding orbiting bodies in outer space. This explanation unified the motion of celestial bodies and the motion of objects on Earth.

Relativistic mechanics

Modern kinematics developed with study of electromagnetism and refers all velocities v

to their ratio to speed of light c

. Velocity is then interpreted as rapidity, the hyperbolic angle φ

for which the hyperbolic tangent function tanh⁡φ=v÷c

. Acceleration, the change of velocity over time, then changes rapidity according to Lorentz transformations. This part of mechanics is special relativity. Efforts to incorporate gravity into relativistic mechanics were made by W. K. Clifford and Albert Einstein. The development used differential geometry to describe a curved universe with gravity; the study is called general relativity.

Quantum mechanics

Quantum mechanics is a set of principles describing physical reality at the atomic level of matter (molecules and atoms) and the subatomic particles (electrons, protons, neutrons, and even smaller elementary particles such as quarks). These descriptions include the simultaneous wave-like and particle-like behavior of both matter and radiation energy as described in the wave–particle duality.

In classical mechanics, accurate measurements and predictions of the state of objects can be calculated, such as location and velocity. In quantum mechanics, due to the Heisenberg uncertainty principle, the complete state of a subatomic particle, such as its location and velocity, cannot be simultaneously determined.

In addition to describing the motion of atomic level phenomena, quantum mechanics is useful in understanding some large-scale phenomena such as superfluidity, superconductivity, and biological systems, including the function of smell receptors and the structures of protein.

Orders of magnitude

Humans, like all known things in the universe, are in constant motion however, aside from obvious movements of the various external body parts and locomotion, humans are in motion in a variety of ways that are more difficult to perceive. Many of these “imperceptible motions” are only perceivable with the help of special tools and careful observation. The larger scales of imperceptible motions are difficult for humans to perceive for two reasons: Newton’s laws of motion (particularly the third), which prevents the feeling of motion on a mass to which the observer is connected, and the lack of an obvious frame of reference that would allow individuals to easily see that they are moving. The smaller scales of these motions are too small to be detected conventionally with human senses.

Universe

Spacetime (the fabric of the universe) is expanding, meaning everything in the universe is stretching, like a rubber band. This motion is the most obscure, not involving physical movement but a fundamental change in the universe’s nature. The primary source of verification of this expansion was provided by Edwin Hubble who demonstrated that all galaxies and distant astronomical objects were moving away from Earth, known as Hubble’s law, predicted by a universal expansion.

Galaxy

The Milky Way Galaxy is moving through space and many astronomers believe the velocity of this motion to be approximately 600 kilometres per second (1,340,000 mph) relative to the observed locations of other nearby galaxies. Another reference frame is provided by the Cosmic microwave background. This frame of reference indicates that the Milky Way is moving at around 582 kilometres per second (1,300,000 mph).

Sun and Solar System

The Milky Way is rotating around its dense Galactic Center, thus the Sun is moving in a circle within the galaxy’s gravity. Away from the central bulge, or outer rim, the typical stellar velocity is between 210 and 240 kilometres per second (470,000 and 540,000 mph). All planets and their moons move with the Sun. Thus, the Solar System is in motion.

Earth

The Earth is rotating or spinning around its axis. This is evidenced by day and night, at the equator the earth has an eastward velocity of 0.4651 kilometres per second (1,040 mph). The Earth is also orbiting around the Sun in an orbital revolution. A complete orbit around the Sun takes one year, or about 365 days; it averages a speed of about 30 kilometres per second (67,000 mph)

Continents

The Theory of Plate tectonics tells us that the continents are drifting on convection currents within the mantle, causing them to move across the surface of the planet at the slow speed of approximately 2.54 centimetres (1 in) per year. However, the velocities of plates range widely. The fastest-moving plates are the oceanic plates, with the Cocos Plate advancing at a rate of 75 millimetres (3.0 in) per year and the Pacific Plate moving 52–69 millimetres (2.0–2.7 in) per year. At the other extreme, the slowest-moving plate is the Eurasian Plate, progressing at a typical rate of about 21 millimetres (0.83 in) per year.

Internal body

The human heart is regularly contracting to move blood throughout the body. Through larger veins and arteries in the body, blood has been found to travel at approximately 0.33 m/s. Though considerable variation exists, and peak flows in the venae cavae have been found between 0.1 and 0.45 metres per second (0.33 and 1.48 ft/s). additionally, the smooth muscles of hollow internal organs are moving. The most familiar would be the occurrence of peristalsis, which is where digested food is forced throughout the digestive tract. Though different foods travel through the body at different rates, an average speed through the human small intestine is 3.48 kilometres per hour (2.16 mph). The human lymphatic system is also constantly causing movements of excess fluids, lipids, and immune system related products around the body. The lymph fluid has been found to move through a lymph capillary of the skin at approximately 0.0000097 m/s.

Cells

The cells of the human body have many structures and organelles that move throughout them. Cytoplasmic streaming is a way in which cells move molecular substances throughout the cytoplasm, various motor proteins work as molecular motors within a cell and move along the surface of various cellular substrates such as microtubules, and motor proteins are typically powered by the hydrolysis of adenosine triphosphate (ATP), and convert chemical energy into mechanical work. Vesicles propelled by motor proteins have been found to have a velocity of approximately 0.00000152 m/s.

Particles

According to the laws of thermodynamics, all particles of matter are in constant random motion as long as the temperature is above absolute zero. Thus the molecules and atoms that make up the human body are vibrating, colliding, and moving. This motion can be detected as temperature; higher temperatures, which represent greater kinetic energy in the particles, feel warm to humans who sense the thermal energy transferring from the object being touched to their nerves. Similarly, when lower temperature objects are touched, the senses perceive the transfer of heat away from the body as a feeling of cold.

Subatomic particles

Within the standard atomic orbital model, electrons exist in a region around the nucleus of each atom. This region is called the electron cloud. According to Bohr’s model of the atom, electrons have a high velocity, and the larger the nucleus they are orbiting the faster they would need to move. If electrons were to move about the electron cloud in strict paths the same way planets orbit the Sun, then electrons would be required to do so at speeds that would far exceed the speed of light. However, there is no reason that one must confine oneself to this strict conceptualization (that electrons move in paths the same way macroscopic objects do), rather one can conceptualize electrons to be ‘particles’ that capriciously exist within the bounds of the electron cloud. Inside the atomic nucleus, the protons and neutrons are also probably moving around due to the electrical repulsion of the protons and the presence of angular momentum of both particles.

Light

Light moves at a speed of 299,792,458 m/s, or 299,792.458 kilometres per second (186,282.397 mi/s), in a vacuum. The speed of light in vacuum is also the speed of all massless particles and associated fields in a vacuum, and it is the upper limit on the speed at which energy, matter, information or causation can travel. The speed of light in vacuum is thus the upper limit for speed for all physical systems.

In addition, the speed of light is an invariant quantity: it has the same value, irrespective of the position or speed of the observer. This property makes the speed of light c a natural measurement unit for speed and a fundamental constant of nature.

In 2019, the speed of light was redefined alongside all seven SI base units using what it calls “the explicit-constant formulation”, where each “unit is defined indirectly by specifying explicitly an exact value for a well-recognized fundamental constant”, as was done for the speed of light. A new, but completely equivalent, wording of the metre’s definition was proposed: “The metre, symbol m, is the unit of length; its magnitude is set by fixing the numerical value of the speed of light in vacuum to be equal to exactly 299792458 when it is expressed in the SI unit m s−1.” This implicit change to the speed of light was one of the changes that was incorporated in the 2019 revision of the SI, also termed the New SI.

Superluminal motion

Some motion appears to an observer to exceed the speed of light. Bursts of energy moving out along the relativistic jets emitted from these objects can have a proper motion that appears greater than the speed of light. All of these sources are thought to contain a black hole, responsible for the ejection of mass at high velocities. Light echoes can also produce apparent superluminal motion. This occurs owing to how motion is often calculated at long distances; oftentimes calculations fail to account for the fact that the speed of light is finite. When measuring the movement of distant objects across the sky, there is a large time delay between what has been observed and what has occurred, due to the large distance the light from the distant object has to travel to reach us. The error in the above naive calculation comes from the fact that when an object has a component of velocity directed towards the Earth, as the object moves closer to the Earth that time delay becomes smaller. This means that the apparent speed as calculated above is greater than the actual speed. Correspondingly, if the object is moving away from the Earth, the above calculation underestimates the actual speed.

Types of motion

Simple harmonic motion – motion in which the body oscillates in such a way that the restoring force acting on it is directly proportional to the body’s displacement. Mathematically Force is directly proportional to the negative of displacement. Negative sign signifies the restoring nature of the force. (e.g., that of a pendulum).
Linear motion – motion that follows a straight linear path, and whose displacement is exactly the same as its trajectory. [Also known as rectilinear motion]
Reciprocal motion
Brownian motion – the random movement of very small particles
Circular motion
Rotatory motion – a motion about a fixed point. (e.g. Ferris wheel).
Curvilinear motion – It is defined as the motion along a curved path that may be planar or in three dimensions.
Rolling motion – (as of the wheel of a bicycle)
Oscillatory – (swinging from side to side)
Vibratory motion
Combination (or simultaneous) motions – Combination of two or more above listed motions
Projectile motion – uniform horizontal motion + vertical accelerated motion

Fundamental motions

Linear motion
Circular motion
Oscillation
Wave
Relative motion
Rotary motion

March 24, 2025

Transport

Transport (in British English) or transportation (in American English) is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land (rail and road), water, cable, pipelines, and space. The field can be divided into infrastructure, vehicles, and operations. Transport enables human trade, which is essential for the development of civilizations.

Transport infrastructure consists of both fixed installations, including roads, railways, airways, waterways, canals, and pipelines, and terminals such as airports, railway stations, bus stations, warehouses, trucking terminals, refueling depots (including fuel docks and fuel stations), and seaports. Terminals may be used both for the interchange of passengers and cargo and for maintenance.

Means of transport are any of the different kinds of transport facilities used to carry people or cargo. They may include vehicles, riding animals, and pack animals. Vehicles may include wagons, automobiles, bicycles, buses, trains, trucks, helicopters, watercraft, spacecraft, and aircraft.

Modes

A mode of transport is a solution that makes use of a certain type of vehicle, infrastructure, and operation. The transport of a person or of cargo may involve one mode or several of the modes, with the latter case being called inter-modal or multi-modal transport. Each mode has its own advantages and disadvantages, and will be chosen on the basis of cost, capability, and route.

Governments deal with the way the vehicles are operated, and the procedures set for this purpose, including financing, legalities, and policies. In the transport industry, operations and ownership of infrastructure can be either public or private, depending on the country and mode.

Passenger transport may be public, where operators provide scheduled services, or private. Freight transport has become focused on containerization, although bulk transport is used for large volumes of durable items. Transport plays an important part in economic growth and globalization, but most types cause air pollution and use large amounts of land. While it is heavily subsidized by governments, good planning of transport is essential to make traffic flow and restrain urban sprawl.

Human-powered

Human-powered transport, a form of sustainable transport, is the transport of people or goods using human muscle-power, in the form of walking, running, and swimming. Modern technology has allowed machines to enhance human power. Human-powered transport remains popular for reasons of cost-saving, leisure, physical exercise, and environmentalism; it is sometimes the only type available, especially in underdeveloped or inaccessible regions.

Although humans are able to walk without infrastructure, the transport can be enhanced through the use of roads, especially when using the human power with vehicles, such as bicycles and inline skates. Human-powered vehicles have also been developed for difficult environments, such as snow and water, by watercraft rowing and skiing; even the air can be entered with human-powered aircraft.

Animal-powered

Animal-powered transport is the use of working animals for the movement of people and commodities. Humans may ride some of the animals directly, use them as pack animals for carrying goods, or harness them, alone or in teams, to pull sleds or wheeled vehicles.

Air

A fixed-wing aircraft, commonly called an airplane, is a heavier-than-air craft where movement of the air in relation to the wings is used to generate lift. The term is used to distinguish this from rotary-wing aircraft, where the movement of the lift surfaces relative to the air generates lift. A gyroplane is both fixed-wing and rotary wing. Fixed-wing aircraft range from small trainers and recreational aircraft to large airliners and military cargo aircraft.

Two things necessary for aircraft are air flow over the wings for lift and an area for landing. The majority of aircraft also need an airport with the infrastructure for maintenance, restocking, and refueling and for the loading and unloading of crew, cargo, and passengers. While the vast majority of aircraft land and take off on land, some are capable of take-off and landing on ice, snow, and calm water.

The aircraft is the second fastest method of transport, after the rocket. Commercial jets can reach up to 955 kilometres per hour (593 mph), single-engine aircraft 555 kilometres per hour (345 mph). Aviation is able to quickly transport people and limited amounts of cargo over longer distances, but incurs high costs and energy use; for short distances or in inaccessible places, helicopters can be used. As of April 28, 2009, The Guardian article notes that “the WHO estimates that up to 500,000 people are on planes at any time.”

Land

Land transport covers all land-based transport systems that provide for the movement of people, goods, and services. Land transport plays a vital role in linking communities to each other. Land transport is a key factor in urban planning. It consists of two kinds, rail and road.

Rail

Rail transport is where a train runs along a set of two parallel steel rails, known as a railway or railroad. The rails are anchored perpendicular to ties (or sleepers) of timber, concrete, or steel, to maintain a consistent distance apart, or gauge. The rails and perpendicular beams are placed on a foundation made of concrete or compressed earth and gravel in a bed of ballast. Alternative methods include monorail and maglev.

A train consists of one or more connected vehicles that operate on the rails. Propulsion is commonly provided by a locomotive, that hauls a series of unpowered cars, that can carry passengers or freight. The locomotive can be powered by steam, by diesel, or by electricity supplied by trackside systems. Alternatively, some or all the cars can be powered, known as a multiple unit. Also, a train can be powered by horses, cables, gravity, pneumatics, and gas turbines. Railed vehicles move with much less friction than rubber tires on paved roads, making trains more energy efficient, though not as efficient as ships.

Intercity trains are long-haul services connecting cities; modern high-speed rail is capable of speeds up to 350 km/h (220 mph), but this requires specially built track. Regional and commuter trains feed cities from suburbs and surrounding areas, while intra-urban transport is performed by high-capacity tramways and rapid transits, often making up the backbone of a city’s public transport. Freight trains traditionally used box cars, requiring manual loading and unloading of the cargo. Since the 1960s, container trains have become the dominant solution for general freight, while large quantities of bulk are transported by dedicated trains

Road

A road is an identifiable route, way, or path between two or more places. Roads are typically smoothed, paved, or otherwise prepared to allow easy travel; though they need not be, and historically many roads were simply recognizable routes without any formal construction or maintenance. In urban areas, roads may pass through a city or village and be named as streets, serving a dual function as urban space easement and route.

The most common road vehicle is the automobile; a wheeled passenger vehicle that carries its own motor. Other users of roads include buses, trucks, motorcycles, bicycles, and pedestrians. As of 2010, there were 1.015 billion automobiles worldwide. Road transport offers complete freedom to road users to transfer the vehicle from one lane to the other and from one road to another according to the need and convenience. This flexibility of changes in location, direction, speed, and timings of travel is not available to other modes of transport. It is possible to provide door-to-door service only by road transport.

Automobiles provide high flexibility with low capacity, but require high energy and area use, and are the main source of harmful noise and air pollution in cities; buses allow for more efficient travel at the cost of reduced flexibility. Road transport by truck is often the initial and final stage of freight transport.

Water

Water transport is movement by means of a watercraft—such as a barge, boat, ship, or sailboat—over a body of water, such as a sea, ocean, lake, canal, or river. The need for buoyancy is common to watercraft, making the hull a dominant aspect of its construction, maintenance, and appearance.

In the 19th century, the first steam ships were developed, using a steam engine to drive a paddle wheel or propeller to move the ship. The steam was produced in a boiler using wood or coal and fed through a steam external combustion engine. Now most ships have an internal combustion engine using a slightly refined type of petroleum called bunker fuel. Some ships, such as submarines, use nuclear power to produce the steam. Recreational or educational craft still use wind power, while some smaller craft use internal combustion engines to drive one or more propellers or, in the case of jet boats, an inboard water jet. In shallow draft areas, hovercraft are propelled by large pusher-prop fans. (See Marine propulsion.)

Although it is slow compared to other transport, modern sea transport is a highly efficient method of transporting large quantities of goods. Commercial vessels, nearly 35,000 in number, carried 7.4 billion tons of cargo in 2007. Transport by water is significantly less costly than air transport for transcontinental shipping; short sea shipping and ferries remain viable in coastal areas.

Other modes

Pipeline transport sends goods through a pipe; most commonly liquid and gases are sent, but pneumatic tubes can also send solid capsules using compressed air. For liquids/gases, any chemically stable liquid or gas can be sent through a pipeline. Short-distance systems exist for sewage, slurry, water, and beer, while long-distance networks are used for petroleum and natural gas.

Cable transport is a broad mode where vehicles are pulled by cables instead of an internal power source. It is most commonly used at steep gradient. Typical solutions include aerial tramways, elevators, and ski lifts; some of these are also categorized as conveyor transport.

Spaceflight is transport outside Earth’s atmosphere by means of a spacecraft. It is most frequently used for satellites placed in Earth orbit. However, human spaceflight mission have landed on the Moon and are occasionally used to rotate crew-members to space stations. Uncrewed spacecraft have also been sent to all the planets of the Solar System.

Suborbital spaceflight is the fastest of the existing and planned transport systems from a place on Earth to a distant “other place” on Earth. Faster transport could be achieved through part of a low Earth orbit or by following that trajectory even faster, using the propulsion of the rocket to steer it.

Elements

Infrastructure

Infrastructure is the fixed installations that allow a vehicle to operate. It consists of a roadway, a terminal, and facilities for parking and maintenance. For rail, pipeline, road, and cable transport, the entire way the vehicle travels must be constructed. Air and watercraft are able to avoid this, since the airway and seaway do not need to be constructed. However, they require fixed infrastructure at terminals.

Terminals such as airports, ports, and stations, are locations where passengers and freight can be transferred from one vehicle or mode to another. For passenger transport, terminals are integrating different modes to allow riders, who are interchanging between modes, to take advantage of each mode’s benefits. For instance, airport rail links connect airports to the city centres and suburbs. The terminals for automobiles are parking lots, while buses and coaches can operate from simple stops. For freight, terminals act as transshipment points, though some cargo is transported directly from the point of production to the point of use.

The financing of infrastructure can either be public or private. Transport is often a natural monopoly and a necessity for the public; roads, and in some countries railways and airports, are funded through taxation. New infrastructure projects can have high costs and are often financed through debt. Many infrastructure owners, therefore, impose usage fees, such as landing fees at airports or toll plazas on roads. Independent of this, authorities may impose taxes on the purchase or use of vehicles. Because of poor forecasting and overestimation of passenger numbers by planners, there is frequently a benefits shortfall for transport infrastructure projects.

Means of transport

Animals

Animals used in transportation include pack animals and riding animals.

Vehicles

A vehicle is a non-living device that is used to move people and goods. Unlike the infrastructure, the vehicle moves along with the cargo and riders. Unless being pulled/pushed by a cable or muscle-power, the vehicle must provide its own propulsion; this is most commonly done through a steam engine, combustion engine, electric motor, jet engine, or rocket, though other means of propulsion also exist. Vehicles also need a system of converting the energy into movement; this is most commonly done through wheels, propellers, and pressure.

Vehicles are most commonly staffed by a driver. However, some systems, such as people movers and some rapid transits, are fully automated. For passenger transport, the vehicle must have a compartment, seat, or platform for the passengers. Simple vehicles, such as automobiles, bicycles, or simple aircraft, may have one of the passengers as a driver. Recently, the progress related to the Fourth Industrial Revolution has brought a lot of new emerging technologies for transportation and automotive fields such as Connected Vehicles and Autonomous Driving. These innovations are said to form future mobility, but concerns remain on safety and cybersecurity, particularly concerning connected and autonomous mobility.

Operation

Private transport is only subject to the owner of the vehicle, who operates the vehicle themselves. For public transport and freight transport, operations are done through private enterprise or by governments. The infrastructure and vehicles may be owned and operated by the same company, or they may be operated by different entities. Traditionally, many countries have had a national airline and national railway. Since the 1980s, many of these have been privatized. International shipping remains a highly competitive industry with little regulation, but ports can be public-owned.

Policy

As the population of the world increases, cities grow in size and population—according to the United Nations, 55% of the world’s population live in cities, and by 2050 this number is expected to rise to 68%. Public transport policy must evolve to meet the changing priorities of the urban world. The institution of policy enforces order in transport, which is by nature chaotic as people attempt to travel from one place to another as fast as possible. This policy helps to reduce accidents and save lives.

Functions

Relocation of travelers and cargo are the most common uses of transport. However, other uses exist, such as the strategic and tactical relocation of armed forces during warfare, or the civilian mobility construction or emergency equipment.

Passenger

Passenger transport, or travel, is divided into public and private transport. Public transport is scheduled services on fixed routes, while private is vehicles that provide ad hoc services at the riders desire. The latter offers better flexibility, but has lower capacity and a higher environmental impact. Travel may be as part of daily commuting or for business, leisure, or migration.

Short-haul transport is dominated by the automobile and mass transit. The latter consists of buses in rural and small cities, supplemented with commuter rail, trams, and rapid transit in larger cities. Long-haul transport involves the use of the automobile, trains, coaches, and aircraft, the last of which have become predominantly used for the longest, including intercontinental, travel. Intermodal passenger transport is where a journey is performed through the use of several modes of transport; since all human transport normally starts and ends with walking, all passenger transport can be considered intermodal. Public transport may also involve the intermediate change of vehicle, within or across modes, at a transport hub, such as a bus or railway station.

Taxis and buses can be found on both ends of the public transport spectrum. Buses are the cheapest mode of transport but are not necessarily flexible, and taxis are very flexible but more expensive. In the middle is demand-responsive transport, offering flexibility whilst remaining affordable.

International travel may be restricted for some individuals due to legislation and visa requirements.

Medical

An ambulance is a vehicle used to transport people from or between places of treatment, and in some instances will also provide out-of-hospital medical care to the patient. The word is often associated with road-going “emergency ambulances”, which form part of emergency medical services, administering emergency care to those with acute medical problems.

Air medical services is a comprehensive term covering the use of air transport to move patients to and from healthcare facilities and accident scenes. Personnel provide comprehensive prehospital and emergency and critical care to all types of patients during aeromedical evacuation or rescue operations, aboard helicopters, propeller aircraft, or jet aircraft.

Freight

Freight transport, or shipping, is a key in the value chain in manufacturing. With increased specialization and globalization, production is being located further away from consumption, rapidly increasing the demand for transport.Transport creates place utility by moving the goods from the place of production to the place of consumption. While all modes of transport are used for cargo transport, there is high differentiation between the nature of the cargo transport, in which mode is chosen. Logistics refers to the entire process of transferring products from producer to consumer, including storage, transport, transshipment, warehousing, material-handling, and packaging, with associated exchange of information. Incoterm deals with the handling of payment and responsibility of risk during transport.

Containerization, with the standardization of ISO containers on all vehicles and at all ports, has revolutionized international and domestic trade, offering a huge reduction in transshipment costs. Traditionally, all cargo had to be manually loaded and unloaded into the haul of any ship or car; containerization allows for automated handling and transfer between modes, and the standardized sizes allow for gains in economy of scale in vehicle operation. This has been one of the key driving factors in international trade and globalization since the 1950s.

Bulk transport is common with cargo that can be handled roughly without deterioration; typical examples are ore, coal, cereals, and petroleum. Because of the uniformity of the product, mechanical handling can allow enormous quantities to be handled quickly and efficiently. The low value of the cargo combined with high volume also means that economies of scale become essential in transport, and gigantic ships and whole trains are commonly used to transport bulk. Liquid products with sufficient volume may also be transported by pipeline.

Air freight has become more common for products of high value; while less than one percent of world transport by volume is by airline, it amounts to forty percent of the value. Time has become especially important in regards to principles such as postponement and just-in-time within the value chain, resulting in a high willingness to pay for quick delivery of key components or items of high value-to-weight ratio. In addition to mail, common items sent by air include electronics and fashion clothing.

Impact

Economic

Transport is a key necessity for specialization—allowing production and consumption of products to occur at different locations. Throughout history, transport has been a spur to expansion; better transport allows more trade and a greater spread of people. Economic growth has always been dependent on increasing the capacity and rationality of transport. But the infrastructure and operation of transport have a great impact on the land, and transport is the largest drainer of energy, making transport sustainability a major issue.

Due to the way modern cities and communities are planned and operated, a physical distinction between home and work is usually created, forcing people to transport themselves to places of work, study, or leisure, as well as to temporarily relocate for other daily activities. Passenger transport is also the essence of tourism, a major part of recreational transport. Commerce requires the transport of people to conduct business, either to allow face-to-face communication for important decisions or to move specialists from their regular place of work to sites where they are needed.

In lean thinking, transporting materials or work in process from one location to another is seen as one of the seven wastes (Japanese term: muda) which do not add value to a product.

Planning

Transport planning allows for high use and less impact regarding new infrastructure. Using models of transport forecasting, planners are able to predict future transport patterns. On the operative level, logistics allows owners of cargo to plan transport as part of the supply chain. Transport as a field is also studied through transport economics, a component for the creation of regulation policy by authorities. Transport engineering, a sub-discipline of civil engineering, must take into account trip generation, trip distribution, mode choice, and route assignment, while the operative level is handled through traffic engineering.

Because of the negative impacts incurred, transport often becomes the subject of controversy related to choice of mode, as well as increased capacity. Automotive transport can be seen as a tragedy of the commons, where the flexibility and comfort for the individual deteriorate the natural and urban environment for all. Density of development depends on mode of transport, with public transport allowing for better spatial use. Good land use keeps common activities close to people’s homes and places higher-density development closer to transport lines and hubs, to minimize the need for transport. There are economies of agglomeration. Beyond transport, some land uses are more efficient when clustered. Transport facilities consume land, and in cities pavement (devoted to streets and parking) can easily exceed 20 percent of the total land use. An efficient transport system can reduce land waste.

Too much infrastructure and too much smoothing for maximum vehicle throughput mean that in many cities there is too much traffic and many—if not all—of the negative impacts that come with it. It is only in recent years that traditional practices have started to be questioned in many places; as a result of new types of analysis which bring in a much broader range of skills than those traditionally relied on—spanning such areas as environmental impact analysis, public health, sociology, and economics—the viability of the old mobility solutions is increasingly being questioned.

Environment

Transport is a major use of energy and burns most of the world’s petroleum. This creates air pollution, including nitrous oxides and particulates, and is a significant contributor to global warming through emission of carbon dioxide, for which transport is the fastest-growing emission sector. According to the International Energy Agency (IEA), the transportation sector accounts for more than one-third of CO2 emissions globally in the early 2020ies. By sub-sector, road transport is the largest contributor to global warming. Environmental regulations in developed countries have reduced individual vehicles’ emissions; however, this has been offset by increases in the numbers of vehicles and in the use of each vehicle. Some pathways to reduce the carbon emissions of road vehicles considerably have been studied. Energy use and emissions vary largely between modes, causing environmentalists to call for a transition from air and road to rail and human-powered transport, as well as increased transport electrification and energy efficiency.

Other environmental impacts of transport systems include traffic congestion and automobile-oriented urban sprawl, which can consume natural habitat and agricultural lands. By reducing transport emissions globally, it is predicted that there will be significant positive effects on Earth’s air quality, acid rain, smog, and climate change.

While electric cars are being built to cut down CO2 emission at the point of use, an approach that is becoming popular among cities worldwide is to prioritize public transport, bicycles, and pedestrian movement. Redirecting vehicle movement to create 20-minute neighbourhoods that promotes exercise while greatly reducing vehicle dependency and pollution. Some policies are levying a congestion charge to cars for travelling within congested areas during peak time.

Airplane emissions change depending on the flight distance. It takes a lot of energy to take off and land, so longer flights are more efficient per mile traveled. However, longer flights naturally use more fuel in total. Short flights produce the most CO2 per passenger mile, while long flights produce slightly less.Things get worse when planes fly high in the atmosphere. Their emissions trap much more heat than those released at ground level. This is not just because of CO2, but a mix of other greenhouse gases in the exhaust.] In 2022 global CO2 emissions from the transport sector grew by more than 250 Mt CO2 to nearly 8 Gt CO2, which represent more than 3% compared to 2021. Aviation was responsible for a significant part of that increase.

City buses produce about 0.3 kg of CO2 for every mile traveled per passenger. For long-distance bus trips (over 20 miles), that pollution drops to about 0.08 kg of CO2 per passenger mile.On average, commuter trains produce around 0.17 kg of CO2 for each mile traveled per passenger. Long-distance trains are slightly higher at about 0.19 kg of CO2 per passenger mile.The fleet emission average for delivery vans, trucks and big rigs is 10.17 kg (22.4 lb) CO2 per gallon of diesel consumed. Delivery vans and trucks average about 7.8 mpg (or 1.3 kg of CO2 per mile) while big rigs average about 5.3 mpg (or 1.92 kg of CO2 per mile

Sustainable development

The United Nations first formally recognized the role of transport in sustainable development in the 1992 United Nations Earth summit. In the 2012 United Nations World Conference, global leaders unanimously recognized that transport and mobility are central to achieving the sustainability targets. In recent years, data has been collected to show that the transport sector contributes to a quarter of the global greenhouse gas emissions, and therefore sustainable transport has been mainstreamed across several of the 2030 Sustainable Development Goals, especially those related to food, security, health, energy, economic growth, infrastructure, and cities and human settlements. Meeting sustainable transport targets is said to be particularly important to achieving the Paris Agreement.

There are various Sustainable Development Goals (SDGs) that are promoting sustainable transport to meet the defined goals. These include SDG 3 on health (increased road safety), SDG 7 on energy, SDG 8 on decent work and economic growth, SDG 9 on resilient infrastructure, SDG 11 on sustainable cities (access to transport and expanded public transport), SDG 12 on sustainable consumption and production (ending fossil fuel subsidies), and SDG 14 on oceans, seas, and marine resources.

Contemporary development studies recognise transportation networks as a key element of economic development, socio-economic well-being and poverty reduction.[57] However, road network development has not always fulfilled its original intentions and has contributed significantly to environmental degradation and, in some cases, led to the loss of cultural traditions and the marginalisation of indigenous peoples. Compared to roads, the development of air links (helicopters and planes) has had an even more devastating impact. What is more, helicopters used for tourist activities are subject to considerable criticism from a perspective of environmental protection as well as sports ethics.

History

Natural

Humans’ first ways to move included walking, running, and swimming. The domestication of animals introduced a new way to lay the burden of transport on more powerful creatures, allowing the hauling of heavier loads, or humans riding animals for greater speed and duration. Inventions such as the wheel and the sled (U.K. sledge) helped make animal transport more efficient through the introduction of vehicles.

The first forms of road transport involved animals, such as horses (domesticated in the 4th or the 3rd millennium BCE), oxen (from about 8000 BCE), or humans carrying goods over dirt tracks that often followed game trails.

Water transport

Water transport, including rowed and sailed vessels, dates back to time immemorial and was the only efficient way to transport large quantities or over large distances prior to the Industrial Revolution. The first watercraft were canoes cut out from tree trunks. Early water transport was accomplished with ships that were either rowed or used the wind for propulsion, or a combination of the two. The importance of water has led to most cities that grew up as sites for trading being located on rivers or on the sea-shore, often at the intersection of two bodies of water.

Mechanical

Until the Industrial Revolution, transport remained slow and costly, and production and consumption gravitated as close to each other as feasible.The Industrial Revolution in the 19th century saw several inventions fundamentally change transport. With telegraphy, communication became instant and independent of the transport of physical objects. The invention of the steam engine, closely followed by its application in rail transport, made land transport independent of human or animal muscles. Both speed and capacity increased, allowing specialization through manufacturing being located independently of natural resources. The 19th century also saw the development of the steam ship, which sped up global transport.

With the development of the combustion engine and the automobile around 1900, road transport became more competitive again, and mechanical private transport originated. The first “modern” highways were constructed during the 19th century with macadam. Later, tarmac and concrete became the dominant paving materials.

In 1903 the Wright brothers demonstrated the first successful controllable airplane, and after World War I (1914–1918) aircraft became a fast way to transport people and express goods over long distances.

After World War II (1939–1945) the automobile and airlines took higher shares of transport, reducing rail and water to freight and short-haul passenger services. Scientific spaceflight began in the 1950s, with rapid growth until the 1970s, when interest dwindled. In the 1950s the introduction of containerization gave massive efficiency gains in freight transport, fostering globalization.[30] International air travel became much more accessible in the 1960s with the commercialization of the jet engine. Along with the growth in automobiles and motorways, rail and water transport declined in relative importance. After the introduction of the Shinkansen in Japan in 1964, high-speed rail in Asia and Europe started attracting passengers on long-haul routes away from the airlines.

Early in U.S. history at 15th century private joint-stock corporations owned most aqueducts, bridges, canals, railroads, roads, and tunnels. Most such transport infrastructure came under government control in the late 19th and early 20th centuries, culminating in the nationalization of inter-city passenger rail-service with the establishment of Amtrak. Recently,[when?] however, a movement to privatize roads and other infrastructure has gained some ground and adherents.

March 24, 2025
Maritime transport
Maritime transport (or ocean transport) or more generally waterborne transport, is the transport of people (passengers) or goods (cargo) via waterways. Freight transport by sea has been widely used throughout recorded history. The advent of aviation has diminished the importance of sea travel for passengers, though it is still popular for short trips and pleasure cruises. Transport by water is cheaper than transport by air or ground, but significantly slower for longer distances. Maritime transport accounts for roughly 80% of international trade, according to UNCTAD in 2020.

Maritime transport can be realized over any distance by boat, ship, sailboat or barge, over oceans and lakes, through canals or along rivers. Shipping may be for commerce, recreation, or military purposes. While extensive inland shipping is less critical today, the major waterways of the world including many canals are still very important and are integral parts of worldwide economies. Particularly, especially any material can be moved by water; however, water transport becomes impractical when material delivery is time-critical such as various types of perishable produce. Still, water transport is highly cost effective with regular schedulable cargoes, such as trans-oceanic shipping of consumer products – and especially for heavy loads or bulk cargos, such as coal, coke, ores, or grains. Arguably, the Industrial Revolution had its first impacts where cheap water transport by canal, navigations, or shipping by all types of watercraft on natural waterways supported cost-effective bulk transport.

Containerization revolutionized maritime transport starting in the 1970s. “General cargo” includes goods packaged in boxes, cases, pallets, and barrels. When a cargo is carried in more than one mode, it is intermodal or co-modal.

Description

A nation’s shipping fleet (variously called merchant navy, merchant marine, or merchant fleet) consists of the ships operated by civilian crews to transport passengers or cargo from one place to another. Merchant shipping also includes water transport over the river and canal systems connecting inland destinations, large and small. For example, during the early modern era, cities in the Hanseatic League began taming Northern Europe’s rivers and harbors. Similarly, the Saint Lawrence Seaway connects the port cities on the Great Lakes in Canada and the United States with the Atlantic Ocean shipping routes, while the various Illinois canals connect the Great Lakes and Canada with New Orleans. Ores, coal, and grains can travel along the rivers of the American Midwest to Pittsburgh or to Birmingham, Alabama. Professional mariners are known as merchant seamen, merchant sailors, and merchant mariners, or simply seamen, sailors, or mariners. The terms “seaman” or “sailor” may also refer to a member of a country’s martial navy.

According to the 2005 CIA World Factbook, the total number of merchant ships of at least 1,000 gross register tons in the world was 30,936. In 2010, it was 38,988, an increase of 26%, across many countries. As of December 2018, a quarter of all merchant mariners were born in the Philippines.

Liners and tramps

A ship may also be categorized as to how it is operated.

A liner will have a regular run and operate to a schedule. The scheduled operation requires that such ships are better equipped to deal with causes of potential delay such as bad weather. They are generally higher powered than tramp ships with better seakeeping qualities, thus they are significantly more expensive to build. Liners are typically built for passenger and container operation though past common uses also included mail and general cargo.

A tramp (trader) has no fixed run but will go wherever a suitable cargo takes it. Thus a ship and crew may be chartered from the ship owner to fetch a cargo of grain from Canada to Latvia, the ship may then be required to carry a cargo of coal from Britain to Melanesia. Bulk carriers and some cruise ships are examples of ships built to operate in this manner.

Ships and watercraft

Ships and other watercraft are used for maritime transport. Types can be distinguished by propulsion, size or cargo type. Recreational or educational craft still use wind power, while some smaller craft use internal combustion engines to drive one or more propellers, or in the case of jet boats, an inboard water jet. In shallow-draft areas, such as the Everglades, some craft, such as the hovercraft, are propelled by large pusher-prop fans.

Bulk carriers (“bulkers”) are cargo ships used to transport bulk cargo items such as ore or food staples (rice, grain, etc.) and similar cargo. They can be recognized by the large box-like hatches on their deck, designed to slide outboard for loading. A bulk carrier could be either dry or wet. Most lakes are too small to accommodate bulk ships, but a large fleet of lake freighters has been plying the Great Lakes and St. Lawrence Seaway of North America for over a century.

Container ships are cargo ships that carry their entire load in truck-sized containers, in a technique called containerization. They form a common means of commercial intermodal freight transport. Informally known as “box boats,” they carry the majority of the world’s dry cargo. Most container ships are propelled by diesel engines and have crews of between 10 and 30 people. They generally have a large accommodation block at the stern, directly above the engine room.

Cruise ships are passenger ships used for pleasure voyages, where the voyage itself and the ship’s amenities are considered an essential part of the experience. Cruising has become a major part of the tourism industry, with millions of passengers each year as of 2006. The industry’s rapid growth has seen nine or more newly built ships catering to a North American clientele added every year since 2001, as well as others servicing European clientele. Smaller markets such as the Asia-Pacific region are generally serviced by older tonnage displaced by new ships introduced into the high growth areas. On the Baltic Sea, ports are connected by cruiseferries.

A multi-purpose ship (sometimes called a general cargo ship) is used to transport a variety of goods, from bulk commodities to break bulk and heavy cargoes. To provide maximum trading flexibility they are usually geared (supplied with cranes), and modern examples are fitted for the carriage of containers and grains. Generally they will have large open holds and tweendecks to facilitate the carriage of different cargoes on the same voyage. The crew will be highly competent in the securing of break bulk cargoes and the ship will be equipped with various lashings and other equipment for sea fastening.

An ocean liner is a passenger ship designed to transport people from one seaport to another along regular long-distance maritime routes according to a schedule. Ocean liners may also carry cargo or mail, and may sometimes be used for other purposes.
Ocean liners are usually strongly built with a high freeboard to withstand rough seas and adverse conditions encountered in the open ocean, having large capacities for fuel, food and other consumables on long voyages. These were the main stay of most passenger transport companies, however, due to the growth of air travel, the passenger ships saw a steady decline. Cruise ships later filled the void and are primarily used by people who still have a love of the sea and offer more amenities than the older passenger ships.

Refrigerated ships (usually called reefers) are cargo ships typically used to transport perishable commodities which require temperature-controlled transportation, mostly fruits, meat, fish, vegetables, dairy products and other foodstuffs.

Roll-on/roll-off ships are ships designed to transport wheeled cargo such as automobiles, trailers or railway carriages. RORO (or ro/ro) vessels have built-in ramps which allow the cargo to be efficiently “rolled on” and “rolled off” the vessel when in port. While smaller ferries that operate across rivers and other short distances still often have built-in ramps, the term RORO is generally reserved for larger ocean-going vessels, including pure car/truck carrier (PCTC) ships.

Tankers are cargo ships for the transport of fluids, such as crude oil, petroleum products, liquefied petroleum gas (LPG), liquefied natural gas (LNG) and chemicals, also vegetable oils, wine and other food. The tanker sector comprises one third of the world tonnage.

Secondary maritime transport types

A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Most barges are not self-propelled and need to be moved by tugboats or towboats pushing or towing them. Barges on canals (towed by draft animals on an adjacent towpath) established the conditions supporting the early Industrial Revolution in both Europe and the American Northeast but later after they made possible steam locomotive prime movers riding iron rails – after both could grow (and mature) to become commonplace and capable – contended with the railways and were outcompeted in the carriage of people, light freight, and high value items due to the higher speed, falling costs, and route flexibility of rail transport. Carriage of bulk goods also gradually lost ground to freight railways as train capacity and speeds continued to climb. Even underpowered early rail networks could usually reach places only an outrageously expensive canal might be built, and once Iron T-rails and higher powered locomotives became possible, the far cheaper to build railways were unfettered and independent upon water sources, whilst mostly unplagued by the seasonal problems (restricted by icing) of temperate latitude canals which suffered ice and freshet flooding damages with dreary regularity. When floods did affect railways, restoration of services was usually comparatively rapid.

Cable layer is a deep-sea vessel designed and used to lay underwater cables for telecommunications, electricity, and such. A large superstructure, and one or more spools that feed off the transom distinguish it. Modern cable layers are equipped with advanced dynamic positioning systems (DPS) to maintain precise control during cable deployment, even in rough sea conditions. These vessels often feature specialized equipment such as remotely operated vehicles (ROVs) to assist with underwater cable positioning, inspections, and repairs.

A dredger (sometimes also called a dredge) is a ship used to excavate in shallow seas or fresh water areas with the purpose of gathering up bottom sediments and disposing of them at a different location, such as for gold exploration.

Ferries are a form of transport, usually a boat or ship, but also other forms, carrying (or ferrying) passengers and sometimes their vehicles. Ferries are also used to transport freight (in lorries and sometimes unpowered freight containers) and even railroad cars. Most ferries operate on regular, frequent return services. A foot-passenger ferry with many stops is sometimes called a waterbus or water taxi. Ferries form a part of the public transport systems of many waterside cities and islands, allowing direct transit between points at a capital cost much lower than bridges or tunnels. Many of the ferries operating in Northern European waters are roll-on/roll-off ships.

A tugboat is a boat used to manoeuvre, primarily by towing or pushing, other vessels (see shipping) in harbours, over the open sea or through rivers and canals. They are also used to tow barges, disabled ships, or other equipment like towboats.

Typical in-transit times

A cargo ship sailing from a European port to a US one will typically take 10–12 days depending on water currents and other factors. In order to make container ship transport more economical, ship operators sometimes reduce cruising speed, thereby increasing transit time, to reduce fuel consumption, a strategy referred to as “slow steaming”.

History

Professional mariners

A ship’s complement can be divided into four categories:
1. The deck department
2. The engine department
3. The steward’s department
4. Other
Deck department

Officer positions in the deck department include but not limited to the Master and his Chief, Second, and Third officers. The official classifications for unlicensed members of the deck department are Able Seaman and Ordinary Seaman.

A common deck crew for a ship includes:

(1) Chief Officer/Chief Mate
(1) Second Officer/Second Mate
(1) Third Officer/Third Mate
(1) Boatswain
(2–6) Able Seamen
(0–2) Ordinary Seamen
A deck cadet is a person who is carrying out mandatory sea time to achieve their officer of the watch certificate. Their time on board is spent learning the operations and tasks of everyday life on a merchant vessel.

Engine department

A ship’s engine department consists of the members of a ship’s crew that operate and maintain the propulsion and other systems on board the vessel. Engine staff also deal with the “Hotel” facilities on board, notably the sewage, lighting, air conditioning and water systems. They deal with bulk fuel transfers, and require training in firefighting and first aid, as well as in dealing with the ship’s boats and other nautical tasks- especially with cargo loading/discharging gear and safety systems, though the specific cargo discharge function remains the responsibility of deck officers and deck workers. On LPG and LNG tankers, however, a cargo engineer works with the deck department during cargo operations, as well as being a watchkeeping engineer.

A common engine crew for a ship includes:

(1) Chief engineer
(1) Second engineer / first assistant engineer
(1) Third engineer / second assistant engineer
(1 or 2) Fourth engineer / third assistant engineer
(0–2) Fifth engineer / junior engineer
(1–3) Oiler (unlicensed qualified rating)
(0–3) Greaser (unlicensed qualified rating)
(1–5) Entry-level rating (such as wiper (occupation), utilityman, etc.)
Many American ships also carry a motorman. Other possible positions include machinist, electrician, refrigeration engineer, and tankerman. Engine cadets are engineer trainees who are completing sea time necessary before they can obtain a watchkeeping license.

Steward’s department

A typical steward’s department for a cargo ship would be composed of a Chief Steward, a chief cook, and a Steward’s Assistant. All three positions are typically filled by unlicensed personnel. The chief steward directs, instructs, and assigns personnel performing such functions as preparing and serving meals; cleaning and maintaining officers’ quarters and steward department areas; and receiving, issuing, and inventorying stores. On large passenger vessels, the Catering Department is headed by the Chief Purser and managed by Assistant Pursers. Although they enjoy the benefits of having officer rank, they generally progress through the ranks to become pursers. Under the pursers are the department heads – such as chief cook, head waiter, head barman etc. They are responsible for the administration of their own areas.

The chief steward also plans menus and compiles supply, overtime, and cost control records. They may requisition or purchase stores and equipment. They may bake bread, rolls, cakes, pies, and pastries. A chief steward’s duties may overlap with those of the Steward’s Assistant, the chief cook, and other Steward’s Department crewmembers.

In the United States Merchant Marine, a chief steward must have a Merchant Mariner’s Document issued by the United States Coast Guard. Because of international law, conventions, and agreements, all chief cooks who sail internationally are similarly documented by their respective countries.

Other departments

Staff officer positions on a ship, including Junior Assistant Purser, Senior Assistant Purser, Purser, Chief Purser, Medical Doctor, Professional Nurse, Marine Physician Assistant, and hospital corpsman, are considered administrative positions and are therefore regulated by Certificates of Registry issued by the United States Coast Guard. Pilots are also merchant marine officers and are licensed by the Coast Guard. Formerly, there was also a radio department, headed by a chief radio officer and supported by a number of radio officers. Since the introduction of GMDSS (Satellite communications) and the subsequent exemptions from carrying radio officers if the vessel is so equipped, this department has fallen away, although many ships do still carry specialist radio officers, particularly passenger vessels. Many radio officers became ‘electro-technical officers’, and transferred into the engine department.

Life at sea

Mariners spend much of their life beyond the reach of land. They sometimes face dangerous conditions at sea or on lakes – the fishing port of Gloucester, Massachusetts has a seaside memorial listing over 10,000 fishermen who lost their lives to the sea, and the Great Lakes have seen over 10,000 lost vessels since the 1800s, yet men and women still go to sea. For some, the attraction is a life unencumbered with the restraints of life ashore. Seagoing adventure and a chance to see the world also appeal to many seafarers. Whatever the calling, those who live and work at sea invariably confront social isolation.

Findings by the Seafarer’s International Research Center indicate a leading cause of mariners leaving the industry is “almost invariably because they want to be with their families.” U.S. merchant ships typically do not allow family members to accompany seafarers on voyages. Industry experts increasingly recognize isolation, stress, and fatigue as occupational hazards. Advocacy groups such as International Labour Organization, a United Nations agency, and the Nautical Institute are seeking improved international standards for mariners. Satellite phones have improved communication and efficiency aboard sea-faring ships. This technology has contributed to crew welfare, although both equipment and fees are expensive.

Ocean voyages are steeped in routine. Maritime tradition dictates that each day be divided into six four-hour periods. Three groups of watch keepers from the engine and deck departments work four hours on then have eight hours off watch keeping. However, there are many overtime jobs to be done daily. This cycle repeats endlessly, 24 hours a day while the ship is at sea. Members of the steward department typically are day workers who put in at least eight-hour shifts. Operations at sea, including repairs, safeguarding against piracy, securing cargo, underway replenishment, and other duties provide opportunities for overtime work. Service aboard ships typically extends for months at a time, followed by protracted shore leave. However, some seamen secure jobs on ships they like and stay aboard for years.

The quick turnaround of many modern ships, spending only a few hours in port, limits a seafarer’s free-time ashore. Moreover, some foreign seamen entering U.S. ports from a watch list of 25 countries face restrictions on shore leave due to maritime security concerns. However, shore leave restrictions while in U.S. ports impact American seamen as well. For example, the International Organization of Masters, Mates & Pilots notes a trend of U.S. shipping terminal operators restricting seamen from traveling from the ship to the terminal gate. Furthermore, in cases where transit is allowed, special “security fees” are at times assessed.

Such restrictions on shore leave, coupled with reduced time in port, translate into longer periods at sea. Mariners report that extended periods at sea living and working with shipmates, who for the most part are strangers, takes getting used to. At the same time, there is an opportunity to meet people from other ethnic and cultural backgrounds. Recreational opportunities have improved aboard some U.S. ships, which may feature gyms and day rooms for watching movies, swapping sea stories, and other activities. And in some cases, especially tankers, it is possible for a mariner to be accompanied by members of his family. However, a mariner’s off-duty time is largely a solitary affair, pursuing hobbies, reading, writing letters, and sleeping.

On modern ocean-going vessels, typically registered with a flag of convenience, life has changed immensely in the last 20 years. Most large vessels include a gym and often a swimming pool for use by the crew. Since the Exxon Valdez incident, the focus of leisure time activity has shifted from having officer and crew bars, to simply having lounge-style areas where officers or crew can sit to watch movies. With many companies now providing TVs and DVD players in cabins, and enforcing strict smoking policies, it is not surprising that the bar is now a much quieter place on most ships. In some instances games consoles are provided for the officers and crew. The officers enjoy a much higher standard of living on board ocean-going vessels.

Crews are generally poorly paid, poorly qualified and have to complete contracts of approximately 9 months before returning home on leave. They often come from countries where the average industrial wage is still very low, such as the Philippines or India. Officers however, come from all over the world and it is not uncommon to mix the nationality of the officers on board ships. Officers are often the recipients of university degrees and have completed vast amounts of training in order to reach their rank. Officers benefit e.g. by having larger, more comfortable cabins and table service for their meals.

Contracts average at the 4 month mark for officers, with generous leave. Most ocean-going vessels now operate an unmanned engine room system allowing engineers to work days only. The engine room is computer controlled by night, although the duty engineer will make inspections during unmanned operation. Engineers work in a hot, humid, noisy atmosphere. Communication in the engine room is therefore by hand signals and lip-reading, and good teamwork often stands in place of any communication at all.

Infrastructure

For a port to efficiently send and receive cargo, it requires infrastructure: docks, bollards, pilings, cranes, bulk cargo handling equipment, and so on – equipment and organization supporting the role of the facilities. From pier to pier these may differ, one dock handling intermodal transport needs (container-ships linked to rail by cranes); another bulk handling capabilities (such as conveyors, elevators, tanks, pumps) for loading and unloading bulk cargoes like grain, coal, or fuels. Others may be outfitted as passenger terminals or for mixed mode operations.

Generally, Harbors, seaports and marinas all host watercraft, and consist of components such as piers, wharfs, docks and roadsteads.

Environmental impact

The environmental impact of shipping includes greenhouse gas emissions, acoustic, and oil pollution. The International Maritime Organization (IMO) estimates that Carbon dioxide emissions from shipping were equal to 2.2% of the global human-made emissions in 2012 and expects them to rise 50 to 250 percent by 2050 if no action is taken. The IEA forecasts that ammonia will meet approximately 45% of shipping fuel demands by 2050.

Innovation and development

The global economy relies heavily on maritime transportation. Maritime transport accounts for over 80% of international trade, according to UNCTAD in 2021, and the percentage is even higher for most developing countries. In its Review of Maritime transport 2024, UNCTAD, points out that the sector, whose greenhouse gas emissions have risen 20% over the last decade, operates an ageing fleet that runs almost exclusively on fossil fuels. Besides, maritime trade is expected to grow 2.4% in 2023 and more than 2% between 2024 and 2028.

Two significant megatrends are observed in terms of maritime transport innovation, sustainability and digitalization. A report published by WIPO in 2024 show a steady increase of patents publication in maritime transportation, the majority of which being related to sustainable propulsion, followed by communication and security.

Transitioning to more sustainable forms of propulsion will help reach decarbonization targets. Technological breakthroughs are advancing low and zero-emission solutions, including more sustainable carbon-based fuels, hydrogen, methanol, ammonia, electric propulsion, and optimizing energy consumption through efficient ship design. However, according to the report, scaling up production and ensuring the cost-effectiveness of carbon-neutral fuels remains a challenge.

Between 2000 and 2023, the number of published patent families in sustainable propulsion increased annually from less than 300 to more than 2,800. In this field, the most important area in terms of patent families is efficient ship design. This includes research activities focused on optimizing hull shape so as to minimize drag, designing efficient propellers or introducing air bubbles under the hull. China is the leader in efficient ship design, batteries and electric propulsion, and the South Korea has published the most patent families in hydrogen/fuel cell research and sustainable fuels. Another important research area is sustainable carbon-based fuels. The vast majority of patents in this area relate to liquified natural gas (LNG) fuels for ships.

Communication and Security technologies are making ships smarter and safer, with key research areas including navigation, device-to-device communication, low-latency communications, cloud platforms, and cybersecurity. Piracy and terror attacks remain a threat in international shipping, with global piracy and armed robbery incidents having increased in 2023 compared to 2022.

Automation and Circularity technologies could boost productivity and enable more energy-efficient ships, with key research themes including efficient material use, smart production and robotics technology, and recycling, but represent a very small area of patenting in the last decade.

Human-Machine-Interface technologies are emerging as useful tools to improve the way we interact with ships. However, all HMI technologies are still in the early stages of development with little adoption in shipping. Research areas include extended reality technologies, speech recognition technology, facial recognition, and touch displays.

Over 70% of all Sea transport patents come from Asia, led by China (36%), the South Korea (25%) and Japan (9%). China’s growth has been on an upward trajectory since 2016, whereas the increase from the South Korea started earlier in 2010 but since 2012 annual filings from Korean inventors have remained relatively stable. Denmark is the most dynamic European nation, followed by Finland, and France, although absolute patent numbers remain relatively small. Only 14% of patents are from Europe and 11% from North America. Top patents owners are companies or universities, such as Harbin Engineering University, Mitsubishi Heavy Industries, Wuhan University of Technology, Gaztransport & Technigaz, Dalian Maritime University, or Dalian Maritime University.
March 24, 2025
Maritime security

Maritime security is an umbrella term informed to classify issues in the maritime domain that are often related to national security, marine environment, economic development, and human security. This includes the world’s oceans but also regional seas, territorial waters, rivers and ports, where seas act as a “stage for geopolitical power projection, interstate warfare or militarized disputes, as a source of specific threats such as piracy, or as a connector between states that enables various phenomena from colonialism to globalization”. The theoretical concept of maritime security has evolved from a narrow perspective of national naval power projection towards a buzzword that incorporates many interconnected sub-fields. The definition of the term maritime security varies and while no internationally agreed definition exists, the term has often been used to describe both existing, and new regional and international challenges to the maritime domain. The buzzword character enables international actors to discuss these new challenges without the need to define every potentially contested aspect of it. Maritime security is of increasing concern to the global shipping industry, where there are a wide range of security threats and challenges. Some of the practical issues clustered under the term of maritime security include crimes such as piracy, armed robbery at sea, trafficking of people and illicit goods, illegal fishing or marine pollution War, warlike activity, maritime terrorism and interstate rivalry (such as the Territorial disputes in the South China Sea or conflict in the Strait of Hormuz) are also maritime security concerns.

While a concern throughout history for nation states, maritime security has evolved significantly since the early 2000s, when in particular concerns over terrorist attacks on port facilities sparked interest in security in the maritime domain and led to the creation of the International Ship and Port Facility Security Code. The ISPS Code is enforced through Chapter XI-2 of the SOLAS Convention. Most littoral states and international organisations have also outlined maritime security strategies. It is in particular piracy in Southeast Asia, off the coast of Somalia and in West Africa which has triggered recognition for the detrimental effects of maritime insecurities for economic development, human security as well as the environment. Maritime security is often transnational and goes beyond the maritime domain itself (see liminality). It is characterized as being cross-jurisdictional and/or highly jurisdictional complex.

History of maritime security

Historically, the sea has been subject to different concepts of law and power. The term mare nostrum (our sea in Latin) was coined by the Romans in 30 BC to 117 AD as a term to describe its control of the Mediterranean Sea. From this concept of the sealing of a sea, the legal concept of mare clausum (closed sea in legal Latin) was developed during the age of discovery between the 15th and 17th century. The sea became a restricted space, organised between Portugal and Spain. Maritime activity was exclusively reserved for the enhancement of national security through naval military. In 1609, Hugo Grotius, a Dutch philosopher and jurist, published the book mare liberum where he introduced the concept of the free sea (mare liberum is translated to free sea in legal Latin). In his book, Grotius laid out the foundation of the freedom of navigation at sea. The sea was seen as international territory, where every nation was free to conduct trade.

Grotius’ concept of the free sea was superseded by the United Nations Convention on the Law of the Sea (UNCLOS). This international agreement first came into effect in 1958 as the Convention on the High Seas (UNCLOS I). The most recent agreement is UNCLOS III, which is active since 1994. It now includes various zones and jurisdictions, including internal, territorial, and archipelagic waters. It further defines the exclusive sovereign waters of a state called contiguous zone, and the exclusive economic zones (EEZs) in which a state has the sole exploitation rights of resources like oil and fish. The latter can be extended by the continental shelf, a natural prolongation of the territory of the respective state.Maritime security has until then been mostly concerned with interstate naval conflicts and piracy at sea.

As a concept and agenda maritime security has evolved since the late 1990s and early 2000s. In particular concerns over terrorist attacks on port facilities sparked new security interests in the maritime domain. Notable events influencing the maritime security paradigm are the USS Cole bombing in 2000 and the September 11 attacks in 2001. Several states and international organisations have since outlined maritime security strategies. Many best practices and standards regarding physical maritime security like the ISPS Code from 2002 as a consequence of the attacks have been published by regulating authorities or the maritime industry. In the light of the perceived terrorist threat, the scope of the maritime security concept began to broaden from the narrow focus on interstate military confrontation to include other issues.

It is in particular the surge of piracy during the early 2000s in Southeast Asia, off the coast of Somalia and in West Africa which has triggered recognition for the detrimental effects of maritime insecurities. As a result of the economic costs for world trade and the physical threats to seafarers, maritime security gained a significant increase of attention by the shipping industry, insurers and policy makers around the world. Piracy was also the starting point of many international relations scholars for approaching maritime security as a concept. In the wake of the Mumbai Terrorist attack in November 2008, an Indian scholar even lamented the serious lack of maritime vision in his government’s policies to preserve India’s expanding interests, thereby coining the catch-phrase “sea-blindness”.

One effect of piracy has been the development of regional cooperation initiatives. In Southeast Asia for example, the Regional Cooperation Agreement on Combating Piracy and Armed Robbery against Ships in Asia (ReCaap) has been initiated in 2004 and includes now an Information Sharing Centre (ISC). Besides maritime domain awareness (MDA) more topics began to become subject of these cooperation initiatives. The International Maritime Organization Djibouti Code of Conduct (DCoC), adopted in 2009, was originally an agreement on cooperation between East African and Southwest Asian states to counter piracy. Since its revision and the complementary Jeddah Amendment to the DCoC of 2017, it now also includes other illicit maritime activities than piracy like human trafficking or illegal, unreported and unregulated fishing (IUU).

Regulatory environment

Maritime security is facilitated at sea and in ports by several international regulations and codes from the International Maritime Organization. The primary Code is the International Ship and Port Facility Security Code which entered into force in 2004. The United Nations Convention on the Laws of the Sea (UNCLOS) which took place in 1984 gives a framework to piracy prohibition. Since 2008, the United Nations Security Council edited some Resolutions concerning the specific Somali case like for example the 1846th in 2008 and the 1918th in 2010, in order to make member countries put piracy as a penal crime in their domestic legislation. Those resolutions were ratified, but despite ratification, few countries have applied that resolution in their domestic law. In 2011, NATO put the maritime security issue in its Alliance Maritime Strategy objectives.

Despite the few countries who applied UN resolutions focused on Somalia piracy in their national legislation, many have created national agencies or bureaus specialized in maritime Security, like the Pakistan Maritime Security Agency in Pakistan. The first country to put the problem on their agenda were the United States in 2004 with the Maritime Security Policy. It marked the beginning of United States’ Maritime Security Operations, some maritime military actions other than wars, charged to detect and prevent illicit operations.

Practical issues of maritime security

Piracy and armed robbery

Piracy and armed robbery remains an ongoing issue in maritime security. The ICC International Maritime Bureau (IMB) Piracy and Armed Robbery report states that attacks against ships and their crews have risen in 2019/2020. They identify that the Gulf of Guinea off West Africa is increasingly dangerous for commercial shipping, accounting for just over 90% of maritime kidnappings worldwide. However, the report noted that the number of ship hijackings in the first half of 2020 was at their lowest level since 1993. In total, IMB’s Piracy Reporting Centre (PRC) recorded 98 incidents of piracy and armed robbery in the first half of 2020, up from 78 in Q2 2019. Some areas of Southeast Asia, including the Straits of Malacca and the Celebes Sea are also areas where piracy and armed robbery take place at sea, although in most cases, armed robbery is the most prevalent.

The West Indian Ocean is an area with maritime security concerns for shipping and governments. Somali piracy started to increase in the early 2000s, after a civil war affected the area. Between 2008 and 2013, large numbers of attacks against merchant ships in the Indian Ocean occurred, gaining international attention. This eventually led to the privatisation of maritime security as an increasing number of shipping companies hired private maritime security companies to protect their crews, ships and cargoes (known as ‘Privately Contracted Armed Security Personnel or PCASP)’. This development affects governments, navies and other security agencies because it is a form of privatised security, one of the core functions of modern states. The maritime industry has developed an ISO certification (ISO 28007:2015) for the provision of privately contracted armed security personnel on board ships. The presence of PCASPs on ships creates complex legal issues and in most cases, permission must be given from the ship’s flag State before armed personnel can attend the vessel and this usually involves confirming Rules for the Use of Force (RUF).

Terrorism

Maritime terrorism is also an issue for maritime security and the definition has been clarified by Council for Security Cooperation in the Asia Pacific as to be “the undertaking of terrorist acts and activities within the maritime environment, using or against vessels or fixed platforms at sea or in port, or against any one of their passengers or personnel, against coastal facilities or settlements, including tourist resorts, port areas and port towns or cities.” The Convention for the Suppression of Unlawful Acts against the Safety of Maritime Navigation, 1988 defines maritime terrorism as “Any attempt or threat to seize control of a ship by force; To damage or destroy a ship or its cargo; To injure or kill a person on board a ship; or To endanger in any way the safe navigation of a ship that moves from the territorial waters”. Some terrorist attacks against maritime targets are very rare compared to the total number of attacks noted by the global terrorism database, however notable cases are famous like the hijacking of the ship Santa Maria in 1961 and the USS Cole bombing in 2000. The September 11 attacks resulted in the global community agreeing on the wider need to improve security in the maritime domain and this led to the creation of the ISPS Code. Since the introduction of the ISPS Code there has not been a major maritime terror attack.

Smuggling and drug trafficking

The illegal drug trade and trafficking of other prohibited items such as weapons is a key issue that affects global maritime security. In particular, Maritime drug trafficking in Latin America is the primary mean of transportation of illegal drugs produced in this region to global consumer markets, primarily in the form of cocaine from the Andean region of South America. The smuggling of drugs through the sea is a security problem for all the countries of the Latin American region. Drug trafficking organizations have developed various complex systems for the transportation and distribution of illegal drugs, where several countries in the region serve as points of contact for the distribution of illegal products, with an estimated 90% of the cocaine produced in the Andean region transported at some point by sea.

Smuggling also includes legally allowed items brought in without declaration to avoid customs charges, such as tobacco. This poses issues for maritime security, as often the smuggling of such items is connected to organised crime. The smuggling of drugs through the sea is a security problem for all the countries of the Latin American region.

While traffickers sometimes make use of narco submarines to transport drugs, the primary method of transfer is utilising existing commercial shipping, either hidden on board or placed within legitimate cargoes such as containers. Large ships present organised criminals with the opportunity to transport high volumes of drugs from producing to consuming countries. The volume of illegal drugs being moved in commercial shipping continues to increase and therefore the risk to ships and ports continues to increase, with ships’ crews often unaware that their ship or its cargo are being used as a cover to transport illegal drugs. However, if illegal drugs are found on board by local customs or law enforcement agencies, innocent companies and seafarers may potentially be exposed to huge financial fines or penalties, or even the risk of imprisonment.

Unsafe mixed migration at sea

Issues such as war, political instability, famine and poverty have resulted in many thousands of people travelling by sea to find better conditions of living. This migration poses several potential security concerns for coastal States, including the safety and legal issues arising from Illegal immigration but also the related criminal aspects of exploitation and human trafficking. Geographic areas principally include the Mediterranean Sea, the Horn of Africa, Southeast Asia and the Caribbean.

Since the beginning of the European migrant crisis in 2015, the effects of unsafe mixed migration on maritime security have been shown by both the number of ships arriving from Africa to the European coast (demonstrating the permeability of Europe’s maritime borders) but also by the visible humanitarian consequences of vessels transporting migrants sinking, leading to deaths at sea.

For shipping, Stowaways remaining a practical security concern while at ports and anchorages. However, the presence of stowaways also presents complex legal issues, involving refugees, the shipping company, ship and ship’s crew, as well as the flag State of the ship and the Port State.

Port security

Port security is part of a broader definition concerning maritime security and refers to the defence, law and treaty enforcement, and counterterrorism activities that fall within the port and surrounding maritime area. It includes the protection of the seaports themselves and the protection and inspection of the cargo moving through the ports. Security risks related to ports often focus on either the physical security of the port, or security risks within the maritime supply chain.[

Interstate conflict

Interstate dispute is a core dimension of maritime security and can be described as a hostile and conflictual relationship between two or more states.Interstate dispute arises due to strategic competition over access and capacity to “to utilise the seas for commercial and military purposes, or to prevent others from doing so”. Interstate disputes vary in nature, scope and severity, yet interstate dispute is always politically motivated and concerns the interests of states’. The concept can be divided into three main categories of disputes; 1) Functional disputes over physical properties and resources at sea, 2) Institutional disputes over territorial boundaries and 3) symbolic disputes over cultural and political values that states attach to the maritime domain.

A present case of interstate rivalry is between the US, India and China in the Western Indian Ocean. The US used to be the dominant naval force in the region, yet this is changing and today the three states are competing over economic influence, extractive resources and military strength in the region.Where the US used to be the dominant security provider of crucial SLOCs in the region India and China are both vying for similar positions today.The increased tensions between have led to increased naval presence and an increasing number of military exercises, which risks intensifying military competition in the region and thus decreasing maritime security in the Western Indian Ocean.

War/Warlike Risks

Armed conflict is an area of maritime security, both in the risks for shipping and users of the sea, but also in the wider context of maritime conflict and Naval warfare. War like risks are of increasing concern for maritime users and governments in areas such as the Persian Gulf. Strait of Hormuz and Southern Red Sea Region where conflicts such as the Yemen Conflict and international events such as the ongoing 2019–2021 Persian Gulf crisis continue to poses maritime security concerns.

Cyber Security

Owing to the increased technology and connectivity on modern ships in the 21st century, cyber security has become a maritime security concern.Cyber Security has come under increased focus in the maritime industry since the IMO required cyber security to be addressed under the International Safety Management Code of ships from 1 January 2021.

There are significant cyber security gaps on ships. These are due to a lack of awareness from ship operators and seafarers. Also, navigation equipment such as ECDIS, GPS, AIS, RADAR can be compromised.

Theoretical approaches to maritime security

Realist’ approach to maritime security

In the traditional realist school of thought of international relations, maritime security is mainly regarded as a matter of sea power (also command of the sea). In peacetime, sea power is associated with countries securing the ability to conduct transport and trade via the sea. In wartime, sea power describes the agency of navies to attack other navies or other countries sea transportation means.

One more recent definitions in realist’ thinking sees maritime security as “The protection of a state’s land and maritime territory, infrastructure, economy, environment and society from certain harmful acts occurring at sea”. Some scholars then argue that maritime security can be classified into two different types, ‘soft’ and ‘hard’ security.

‘Hard’ maritime security signifying sea power and domination of the sea and ‘soft’ maritime security being used for threats concerning “ocean resources, transportation and trade, and exchange of information”.

A number of constructivist’ scholars have criticised this approach to maritime security where defining what a maritime security issue actually is, often becomes a collection of topics associated with threats in the maritime domain. The US Naval Operations Concept from 2006 for example listed “ensuring the freedom of navigation, the flow of commerce and the protection of ocean resources, as well as securing the maritime domain from nation-state threats, terrorism, drug trafficking and other forms of transnational crime, piracy, environmental destruction and illegal seaborne immigration as the goal of maritime security.

Liberalist’ approach to maritime security

Central to the liberal school of thought approach in international relations to maritime security is the regulation of the maritime domain. Some legal scholars have defined maritime security as a “stable order of the oceans subject to the rule of law at sea”. The liberalist’ approach emphasises that international law has been a means to transform the traditional way of countries power projection on the sea through their navies towards a cooperation in order to achieve common goals. The focus of the liberal paradigm has been criticised as being mainly limited to technicalities and formalities of international law, but not helping understanding the governance aspects of maritime security that go beyond legal and normative regulation.

However, it has also been pointed out that the liberalist approach is a much better reflection of reality than the highly theoretical constructivist approach, explained in detail below. Dirk Siebels, an expert on maritime security, has explained that regional agreements between governments are generally needed to define maritime security – or good order at sea – for the respective region. Governments in West Africa, Southeast Asia, Europe or other regions may have different priorities, “yet it is their order, defined in negotiations and in line with international law”.

Constructivist’ approach to maritime security

Constructivism is based on the notion, that security is a socially constructed concept. Rather than accepting maritime security as a given list of threats and means, the constructivist school of thought is interested in looking at the relations and how the concept of maritime security comes to be through actions, interactions and perceptions. Constructivists’ look at how different understandings of maritime security are informed by different political interests and normative understandings.

Professor Christian Bueger has proposed three frameworks for how to deconstruct concepts of maritime security by various actors: the maritime security matrix that helps conceptualise relations, the securitization framework that looks at claims that are being made in relation to maritime security, and practice theory to analyse what is actually being done in the name of maritime security.

Maritime security matrix

The maritime security matrix looks at the semantic relations between maritime security and other maritime concepts using four dimensions to relate and situate maritime security topics in and to the general concept of ‘maritime security’:

Marine environment (e.g. connected to marine safety)
Economic development (e.g. connected to blue economy)
National security (e.g. connected to seapower)
Human security (e.g. connected to human trafficking)

A matrix may have each concept in a corner of a square, maritime security being situated in the centre. Depending on what is being analysed, concepts like human trafficking can then be situated e.g. between ‘maritime security’, ‘human security’, and ‘economic development’.

Securitization framework

Securitization is a framework of international relations originally developed by Ole Wæver and Barry Buzan. Sometimes called the Copenhagen School, securitization looks at who is making claims (using some form of language) in the name of security to carryout measures that would otherwise not easily be justified and accepted.

Practice theory

The framework of practice theory enables to analyse what kind of activities are actually conducted in the name of security. Practice in this theory is seen as patterns of doing and saying things that lead to the implementation of maritime security measures. According to Bueger five practices fit within the conventional spectrum of maritime security:

Maritime domain awareness (MDA, see also Information Sharing Centre (ISC))
Activities at sea (e.g. patrols, inspections, exercises)
Law enforcement activities (e.g. arrests, trials and prosecutions)
Coordination activities (e.g. forums, conferences, harmonizing legal frameworks)
Naval diplomacy (e.g. capacity building, warfare) This type of activity might not be associated with maritime security, but rather with war or other related concepts.

These activities can be seen through two different perspective. The focus can either be laid on what activities belong to the everyday routine of maritime security actors or on the measures that are done in exceptional circumstances.

March 24, 2025

United States Coast Guard

The United States Coast Guard (USCG) is the maritime security, search and rescue, and law enforcement service branch of the armed forces of the United States. It is one the country’s eight uniformed services. The service is a maritime, military, multi-mission service unique among the United States military branches for having a maritime law enforcement mission with jurisdiction in both domestic and international waters and a federal regulatory agency mission as part of its duties. It is the largest coast guard in the world, rivaling the capabilities and size of most navies.

The U.S. Coast Guard protects the United States’ borders and economic and security interests abroad; and defends its sovereignty by safeguarding sea lines of communication and commerce across U.S. territorial waters and its Exclusive Economic Zone. Due to ever-expanding risk imposed by transnational threats through the maritime and cyber domains, the U.S. Coast Guard is at any given time deployed to and operating on all seven continents and in cyberspace to enforce its mission. Like its United States Navy sibling, the U.S. Coast Guard maintains a global presence with permanently-assigned personnel throughout the world and forces routinely deploying to both littoral and blue-water regions. The U.S. Coast Guard’s adaptive, multi-mission “white hull” fleet is leveraged as a force of both diplomatic soft power and humanitarian and security assistance over the more overtly confrontational nature of “gray hulled” warships. As a humanitarian service, it saves tens of thousands of lives a year at sea and in U.S. waters, and provides emergency response and disaster management for a wide range of human-made and natural catastrophic incidents in the U.S. and throughout the world.

The U.S. Coast Guard operates under the U.S. Department of Homeland Security during peacetime. During times of war, it can be transferred in whole or in part to the U.S. Department of the Navy under the Department of Defense by order of the U.S. president or by act of Congress. Prior to its transfer to Homeland Security, it operated under the Department of Transportation from 1967 to 2003 and the Department of the Treasury from its inception until 1967. A congressional authority transfer to the Navy has only happened once: in 1917, during World War I. By the time the U.S. entered World War II in December 1941, the U.S. Coast Guard had already been transferred to the Navy by President Franklin Roosevelt.

Created by Congress as the Revenue-Marine on 4 August 1790 at the request of Alexander Hamilton, it is the oldest continuously operating naval service of the United States.As secretary of the treasury, Hamilton headed the Revenue-Marine, whose original purpose was collecting customs duties at U.S. seaports. By the 1860s, the service was known as the U.S. Revenue Cutter Service and the term Revenue-Marine gradually fell into disuse.

The modern U.S. Coast Guard was formed by a merger of the U.S. Revenue Cutter Service and the U.S. Life-Saving Service on 28 January 1915, under the Department of the Treasury. In 1939, the U.S. Lighthouse Service was also merged into the U.S. Coast Guard. As one of the country’s six armed services, the U.S. Coast Guard and its predecessor have participated in every major U.S. war since 1790, from the Quasi-War with France to the Global War on Terrorism.

As of December 2021, the U.S. Coast Guard’s authorized force strength is 44,500 active duty personnel and 7,000 reservists.The service’s force strength also includes 8,577 full-time civilian federal employees and 21,000 uniformed civilian volunteers of the U.S. Coast Guard Auxiliary. The service maintains an extensive fleet of roughly 250 coastal and ocean-going cutters, patrol ships, buoy tenders, tugs, and icebreakers; as well as nearly 2,000 small boats and specialized craft. It also maintains an aviation division consisting of more than 200 helicopters and fixed-wing aircraft. While the U.S. Coast Guard is the second smallest of the U.S. military service branches in terms of membership, the service by itself is the world’s 12th largest naval force.

Mission

Role

The Coast Guard carries out three basic roles, which are further subdivided into eleven statutory missions. The three roles are:

Maritime safety
Maritime security
Maritime stewardship

With a decentralized organization and much responsibility placed on even the most junior personnel, the Coast Guard is frequently lauded for its quick responsiveness and adaptability in a broad range of emergencies. In a 2005 article in Time magazine following Hurricane Katrina, the author wrote, “the Coast Guard’s most valuable contribution to [a military effort when catastrophe hits] may be as a model of flexibility, and most of all, spirit.” Wil Milam, a rescue swimmer from Alaska told the magazine, “In the Navy, it was all about the mission. Practicing for war, training for war. In the Coast Guard, it was, take care of our people and the mission will take care of itself.”

Missions

The eleven statutory missions as defined by law are divided into homeland security missions and non-homeland security missions:

Non-homeland security missions

Ice operations, including the International Ice Patrol
Living marine resources (fisheries law enforcement)
Marine environmental protection
Marine safety
Aids to navigation
Search and rescue

Homeland security missions

Defense readiness
Maritime law enforcement
Migrant interdiction
Ports, waterways and coastal security (PWCS)
Drug interdiction

Search and rescue

The U.S. Coast Guard Search and Rescue (CG-SAR) is one of the Coast Guard’s best-known operations. The National Search and Rescue Plan designates the Coast Guard as the federal agency responsible for maritime SAR operations, and the United States Air Force as the federal agency responsible for inland SAR. Both agencies maintain rescue coordination centers to coordinate this effort, and have responsibility for both military and civilian search and rescue. The two services jointly provide instructor staff for the National Search and Rescue School that trains SAR mission planners and coordinators. Previously located on Governors Island, New York, the school is now located at Coast Guard Training Center Yorktown at Yorktown, Virginia.

National Response Center

Operated by the Coast Guard, the National Response Center (NRC) is the sole U.S. Government point of contact for reporting all oil, chemical, radiological, biological, and etiological spills and discharges into the environment, anywhere in the United States and its territories. In addition to gathering and distributing spill/incident information for Federal On Scene Coordinators and serving as the communications and operations center for the National Response Team, the NRC maintains agreements with a variety of federal entities to make additional notifications regarding incidents meeting established trigger criteria. The NRC also takes Maritime Suspicious Activity and Security Breach Reports. Details on the NRC organization and specific responsibilities can be found in the National Oil and Hazardous Substances Pollution Contingency Plan. The Marine Information for Safety and Law Enforcement (MISLE) database system is managed and used by the Coast Guard for tracking pollution and safety incidents in the nation’s ports.

National Maritime Center

The National Maritime Center (NMC) is the merchant mariner credentialing authority for the USCG under the auspices of the Department of Homeland Security. To ensure a safe, secure, and environmentally sound marine transportation system, the mission of the NMC is to issue credentials to fully qualified mariners in the United States maritime jurisdiction.

Authority as an armed service

Title 10 of the U.S. Code says that “the term “armed forces” means the Army, Marine Corps, Navy, Air Force, Space Force, and Coast Guard.”The Coast Guard is further defined by Title 14 of the United States Code: “The Coast Guard as established January 28, 1915, shall be a military service and a branch of the armed forces of the United States at all times. The Coast Guard shall be a service in the Department of Homeland Security, except when operating as a service in the Navy.” Coast Guard organization and operation is as set forth in Title 33 of the Code of Federal Regulations.

On 25 November 2002, the Homeland Security Act was signed into law by U.S. President George W. Bush, designating the Coast Guard to be placed under the U.S. Department of Homeland Security. The transfer of administrative control from the U.S. Department of Transportation to the U.S. Department of Homeland Security was completed the following year, on 1 March 2003.

The U.S. Coast Guard reports directly to the civilian secretary of homeland security. However, under 14 U.S.C. § 3 as amended by section 211 of the Coast Guard and Maritime Transportation Act of 2006, upon the declaration of war and when Congress so directs in the declaration, or when the president directs, the Coast Guard operates under the Department of Defense as a service in the Department of the Navy.

As members of the military, coast guardsmen on active and reserve service are subject to the Uniform Code of Military Justice and receive the same pay and allowances as members of the same pay grades in the other uniformed services.

The service has participated in every major U.S. conflict from 1790 through today, including landing troops on D-Day and on the Pacific Islands in World War II, in extensive patrols and shore bombardment during the Vietnam War, and multiple roles in Operation Iraqi Freedom. Maritime interception operations, coastal security, transportation security, and law enforcement detachments have been its major roles in recent conflicts in Iraq.

On 17 October 2007, the Coast Guard joined with the U.S. Navy and U.S. Marine Corps to adopt a new maritime strategy called A Cooperative Strategy for 21st Century Seapower that raised the notion of prevention of war to the same philosophical level as the conduct of war. This new strategy charted a course for the Navy, Coast Guard and Marine Corps to work collectively with each other and international partners to prevent regional crises, man-made or natural, from occurring, or reacting quickly should one occur to avoid negative impacts to the United States. During the launch of the new U.S. maritime strategy at the International Seapower Symposium at the U.S. Naval War College in 2007, Coast Guard commandant admiral Thad Allen said the new maritime strategy reinforced the time-honored missions the service has carried out in the United States since 1790. “It reinforces the Coast Guard maritime strategy of safety, security and stewardship, and it reflects not only the global reach of our maritime services but the need to integrate and synchronize and act with our coalition and international partners to not only win wars … but to prevent wars,” Allen said.

Authority as a law enforcement agency

Title 14 USC, section 2 authorizes the Coast Guard to enforce U.S. federal laws. This authority is further defined in 14 U.S.C. § 522, which gives law enforcement powers to all Coast Guard commissioned officers, warrant officers, and petty officers. Unlike the other armed forces branches, which are prevented from acting in a law enforcement capacity by 18 U.S.C. § 1385, the Posse Comitatus Act, and Department of Defense policy, the Coast Guard is exempt from and not subject to the restrictions of the Posse Comitatus Act.

Further law enforcement authority is given by 14 U.S.C. § 703 and 19 U.S.C. § 1401, which empower U.S. Coast Guard active and reserve commissioned officers, warrant officers, and petty officers as federal customs officers. This places them under 19 U.S.C. § 1589a, which grants customs officers general federal law enforcement authority, including the authority to:

(1) carry a firearm;
(2) execute and serve any order, warrant, subpoena, summons, or other process issued under the authority of the United States;
(3) make an arrest without a warrant for any offense against the United States committed in the officer’s presence or for a felony, cognizable under the laws of the United States committed outside the officer’s presence if the officer has reasonable grounds to believe that the person to be arrested has committed or is committing a felony; and
(4) perform any other law enforcement duty that the Secretary of Homeland Security may designate.

— 19 USC §1589a. Enforcement authority of customs officers

The U.S. Government Accountability Office Report to the House of Representatives, Committee on the Judiciary on its 2006 Survey of Federal Civilian Law Enforcement Functions and Authorities, identified the Coast Guard as one of 104 federal components that employed law enforcement officers. The report also included a summary table of the authorities of the Coast Guard’s 192 special agents and 3,780 maritime law enforcement boarding officers.

Coast Guardsmen have the legal authority to carry their service-issued firearms on and off base. This is rarely done in practice, however; at many Coast Guard stations, commanders prefer to have all service-issued weapons in armories when not in use. Still, one court has held in the case of People v. Booth that Coast Guard boarding officers are qualified law enforcement officers authorized to carry personal firearms off-duty for self-defense.

History

The Coast Guard traced its roots to the small fleet of vessels maintained by the United States Department of the Treasury beginning in the 1790s to enforce tariffs (an important source of revenue for the new nation). Secretary of the Treasury Alexander Hamilton lobbied Congress to fund the construction of ten cutters, which it did on 4 August 1790 (now celebrated as the Coast Guard’s official birthday). Until the re-establishment of the Navy in 1798, these “revenue cutters” were the only naval force of the early United States. As such, the cutters and their crews frequently took on additional duties, including combating piracy, rescuing mariners in distress, ferrying government officials, and even carrying mail. Initially not an organized federal agency at all, merely a “system of cutters,” each ship operated under the direction of the customs officials in the port to which it was assigned. Several names, including “Revenue-Marine,” were used as the service gradually becoming more organized. Eventually it was officially organized as the United States Revenue Cutter Service. In addition to its regular law enforcement and customs duties, revenue cutters and their crews were used to support and supplement the Navy in various armed conflicts including the American Civil War.

A separate federal agency, the U.S. Life-Saving Service, developed alongside the Revenue-Marine. Prior to 1848, there were various charitable efforts at creating systems to provide assistance to shipwrecked mariners from shore-based stations, notably by the Massachusetts Humane Society. The federal government began funding lifesaving stations in 1848 but funding was inconsistent and the system still relied on all-volunteer crews. In 1871, Sumner Increase Kimball was appointed chief of the Treasury Department’s newly created Revenue Marine Division, and began the process of organizing the Revenue-Marine cutters into a centralized agency. Kimball also pushed for more funding lifesaving stations and eventually secured approval to create the Lifesaving Service as a separate federal agency, also within the Treasury Department, with fulltime paid crews.

In 1915 these two agencies, the Revenue Cutter Service and the Lifesaving Service, were merged to create the modern United States Coast Guard. The Lighthouse Service and the Bureau of Marine Inspection and Navigation were absorbed by the Coast Guard 1939 and 1942 respectively. In 1967, the Coast Guard moved from the U.S. Department of the Treasury to the newly formed U.S. Department of Transportation, an arrangement that lasted until it was placed under the U.S. Department of Homeland Security in 2003 as part of legislation designed to more efficiently protect American interests following the terrorist attacks of 11 September 2001.

In times of war, the Coast Guard or individual components of it can operate as a service of the Department of the Navy. This arrangement has a broad historical basis, as the Coast Guard has been involved in wars as diverse as the War of 1812, the Mexican–American War, and the American Civil War, in which the cutter Harriet Lane fired the first naval shots attempting to relieve besieged Fort Sumter. The last time the Coast Guard operated as a whole within the Navy was in World War II, in all some 250,000 served in the Coast Guard during World War II.

Coast Guard Squadron One, was a combat unit formed by the United States Coast Guard in 1965 for service during the Vietnam War. Placed under the operational control of the United States Navy, it was assigned duties in Operation Market Time. Its formation marked the first time since World War II that Coast Guard personnel were used extensively in a combat environment. The squadron operated divisions in three separate areas during the period of 1965 to 1970. Twenty-six Point-class cutters with their crews and a squadron support staff were assigned to the U.S. Navy with the mission of interdicting the movement of arms and supplies from the South China Sea into South Vietnam by Viet Cong and North Vietnam junk and trawler operators. The squadron also provided 81mm mortar naval gunfire support to nearby friendly units operating along the South Vietnamese coastline and assisted the U.S. Navy during Operation Sealords.

Coast Guard Squadron Three, was a combat unit formed by the United States Coast Guard in 1967 for service during the Vietnam War. Placed under the operational control of the United States Navy and based in Pearl Harbor. It consisted of five USCG High Endurance Cutters operating on revolving six-month deployments. A total of 35 High Endurance Cutters took part in operations from May 1967 to December 1971, most notably using their 5-inch guns to provide naval gunfire support missions.

Often units within the Coast Guard operate under Department of the Navy operational control while other Coast Guard units remain under the Department of Homeland Security.

Deployable Operations Group/Deployable Specialized Forces

The Deployable Operations Group (DOG) was a Coast Guard command established in July 2007. The DOG established a single command authority to rapidly provide the Coast Guard, Department of Homeland Security, Department of Defense, Department of Justice and other interagency operational commanders adaptive force packages drawn from the Coast Guard’s deployable specialized force units. The DOG was disestablished on 22 April 2013 and reorganized into Deployable Specialized Forces (DSF) units were placed under the control of the Atlantic and Pacific Area Commanders.

The planning for the unit began after the terrorist attacks of 11 September 2001, and culminated with its formation on 20 July 2007. Its missions included maritime law enforcement, anti-terrorism, port security, pollution response, and diving operations.

There were over 25 specialized units within the Deployable Operations Group including the Maritime Security Response Team, Maritime Safety and Security Teams, Law Enforcement Detachments, Port Security Units, the National Strike Force, and Regional Dive Lockers. The DOG also managed Coast Guard personnel assigned to the Navy Expeditionary Combat Command and was involved in the selection of Coast Guard candidates to attend Navy BUD/S and serve with Navy SEAL Teams.

Organization

The new Department of Homeland Security headquarters complex is on the grounds of the former St. Elizabeths Hospital in the Anacostia section of Southeast Washington, across the Anacostia River from former Coast Guard headquarters.

The fiscal year 2016 budget request for the U.S. Coast Guard was $9.96 billion

Districts and units

The Coast Guard’s current district organization is divided into 9 districts. Their designations, district office and area of responsibility are as follows:

U.S. Coast Guard districts

District	District Office	Area of responsibility

1st

Boston, Massachusetts

New England states, eastern New York and northern New Jersey

5th

Portsmouth, Virginia

Pennsylvania, southern New Jersey, Delaware, Maryland, Virginia, and North Carolina

7th

Miami, Florida

South Carolina, Georgia, eastern Florida, Puerto Rico,
and the U.S. Virgin Islands

8th

New Orleans, Louisiana

Western Rivers of the U.S. and the Gulf of Mexico

California, Arizona, Nevada, and Utah

13th

Seattle, Washington

Oregon, Washington, Idaho and Montana

14th

Honolulu, Hawaii

Hawaii and Pacific territories

17th

Juneau, Alaska

Alaska

Shore establishments

Shore establishment commands exist to support and facilitate the mission of the sea and air assets and Coastal Defense. U.S. Coast Guard Headquarters is located in Southeast Washington, D.C. Examples of other shore establishment types are Coast Guard Sectors (which may include Coast Guard Bases), Surface Forces Logistics Center (SFLC), Coast Guard Stations, Coast Guard Air Stations, and the United States Coast Guard Yard. Training centers are included in the shore establishment commands. The military college for the USCG is called the United States Coast Guard Academy which trains both new officers through a four year program and enlisted personnel joining the ranks of officers through a 17 week program called Officer Candidate School (OCS). Abbreviated TRACEN, the other Training Centers include Training Center Cape May for enlisted bootcamp, Training Center Petaluma and Training Center Yorktown for enlisted “A” schools and “C” schools, and Coast Guard Avation Technical Training Center and Coast Guard Aviation Training Center Mobile for aviation enlisted “A” school, “C” schools, and pilot officer training.

Personnel

The Coast Guard has a total workforce of 87,569. The formal name for a uniformed member of the Coast Guard is “coast guardsman”, irrespective of gender. “Coastie” is an informal term commonly used to refer to current or former Coast Guard personnel. In 2008, the term “guardian” was introduced as an alternative but was later dropped. Admiral Robert J. Papp Jr. stated that it was his belief that no Commandant had the authority to change what members of the Coast Guard are called as the term coast guardsman is found in Title 14 USC which established the Coast Guard in 1915.”Team Coast Guard” refers to the four components of the Coast Guard as a whole: Regular, Reserve, Auxiliary, and Coast Guard civilian employees.

Commissioned officers

Commissioned officers in the Coast Guard hold pay grades ranging from O-1 to O-10 and have the same rank structure as the Navy. Officers holding the rank of ensign (O-1) through lieutenant commander (O-4) are considered junior officers, commanders (O-5) and captains (O-6) are considered senior officers, and rear admirals (O-7) through admirals (O-10) are considered flag officers. The commandant of the Coast Guard and the vice commandant of the Coast Guard are the only members of the Coast Guard authorized to hold the rank of admiral.

The Coast Guard does not have medical officers or chaplains of its own. Instead, chaplains from the U.S. Navy, as well as officers from the U.S. Public Health Service Commissioned Corps are assigned to the Coast Guard to perform chaplain-related functions and medical-related functions, respectively. These officers wear Coast Guard uniforms but replace the Coast Guard insignia with that of their own service.

The Navy and Coast Guard share identical officer rank insignia except that Coast Guard officers wear a gold Coast Guard Shield in lieu of a line star or staff corps officer insignia.

Warrant officers

Highly qualified enlisted personnel in pay grades E-6 through E-9 with a minimum of eight years’ experience can compete each year for appointment as warrant officers (WO). Successful candidates are chosen by a board and then commissioned as chief warrant officer two (CWO2) in one of twenty-one specialties. Over time, chief warrant officers may be promoted to chief warrant officer three (CWO3) and chief warrant officer four (CWO4). The ranks of warrant officer (WO1) and chief warrant officer five (CWO5) are not currently used in the Coast Guard. Chief warrant officers may also compete for the Chief Warrant Officer to Lieutenant Program. If selected, the warrant officer will be promoted to lieutenant (O-3E). The “E” designates over four years’ active duty service as a warrant officer or enlisted member and entitles the member to a higher rate of pay than other lieutenants.

Enlisted personnel

Enlisted members of the Coast Guard have pay grades from E-1 to E-9 and also follow the same rank structure as the Navy. Enlisted members in pay grades of E-4 and higher are considered petty officers and follow career development paths very similar to those of Navy petty officers.

Petty officers in pay grade E-7 and higher are chief petty officers and must attend the Coast Guard Chief Petty Officer Academy, or an equivalent Department of Defense school, in order to be advanced to pay grade E-8. The basic themes of the school are:

Professionalism
Leadership
Communications
Systems thinking and lifelong learning

Enlisted rank insignia is also nearly identical to Navy enlisted insignia. The Coast Guard shield replacing the petty officer’s eagle on collar and cap devices for petty officers or enlisted rating insignia for seamen qualified as a “designated striker”. Group Rate marks (stripes) for junior enlisted members (E-3 and below) also follow Navy convention with white for seaman, red for fireman, and green for airman. In a departure from the Navy conventions, all petty officers E-6 and below wear red chevrons and all chief petty officers wear gold.

Training

Officer training

The U.S. Coast Guard Academy is a four-year service academy located in New London, Connecticut. Approximately 200 cadets graduate each year, receiving a Bachelor of Science degree and a commission as an ensign in the Coast Guard. Graduates are obligated to serve a minimum of five years on active duty. Most graduates are assigned to duty aboard Coast Guard cutters immediately after graduation, either as Deck Watch Officers (DWOs) or as Engineer Officers in Training (EOITs). Smaller numbers are assigned directly to flight training at Naval Air Station Pensacola, Florida or to shore duty at Coast Guard Sector, District, or Area headquarters units.

In addition to the Academy, prospective officers, who already hold a college degree, may enter the Coast Guard through Officer Candidate School (OCS), also located at the Coast Guard Academy. OCS is a 17-week course of instruction that prepares candidates to serve effectively as officers in the Coast Guard. In addition to indoctrinating students into a military lifestyle, OCS provides a wide range of highly technical information necessary to perform the duties of a Coast Guard officer.

Graduates of OCS are usually commissioned as ensigns, but some with advanced graduate degrees may enter as lieutenants (junior grade) or lieutenants. Graduating OCS officers entering active duty are required to serve a minimum of three years, while graduating reserve officers are required to serve four years. Graduates may be assigned to a cutter, flight training, a staff job, or an operations ashore billet. OCS is the primary channel through which the Coast Guard enlisted grades ascend to the commissioned officer corps. Unlike the other military services, the Coast Guard does not have a Reserve Officers’ Training Corps (ROTC) program.However, the Coast Guard does have the Select Reserve Direct Commission, an officer program for prospective candidates interested serving as a Coast Guard Reserve Officer.

Lawyers, engineers, intelligence officers, military aviators holding commissions in other branches of the U.S. Armed Forces requesting interservice transfers to the Coast Guard, graduates of maritime academies, and certain other individuals may also receive an officer’s commission in the Coast Guard through the Direct Commission Officer (DCO) program. Depending on the specific program and the background of the individual, the course is three, four or five weeks long. The first week of the five-week course is an indoctrination week. The DCO program is designed to commission officers with highly specialized professional training or certain kinds of previous military experience.

Recruit training

Newly enlisted personnel are sent to eight weeks of recruit training at Coast Guard Training Center Cape May in Cape May, New Jersey. New recruits arrive at Sexton Hall and remain there for three days of initial processing which includes haircuts, vaccinations, uniform issue, and other necessary entrance procedures. During this initial processing period, the new recruits are led by temporary company commanders. These temporary company commanders are tasked with teaching the new recruits how to march and preparing them to enter into their designated company. The temporary company commanders typically do not enforce any physical activity such as push ups or crunches. When the initial processing is complete, the new seaman recruits are introduced to their permanent company commanders who will remain with them until the end of training. There is typically a designated lead company commander and two support company commanders. The balance of the eight-week boot camp is spent in learning teamwork and developing physical skills. An introduction of how the Coast Guard operates with special emphasis on the Coast Guard’s core values is an important part of the training.

The current nine Recruit Training Objectives are:

Self-discipline
Military skills
Marksmanship
Vocational skills and academics
Military bearing
Physical fitness and wellness
Water survival and swim qualifications
Esprit de corps
Core values (Honor, Respect, and Devotion to Duty)

Service schools

Following graduation from recruit training, most members are sent to their first unit while they await orders to attend advanced training in Class “A” Schools. At “A” schools, Coast Guard enlisted personnel are trained in their chosen rating; rating is a Coast Guard and Navy term for enlisted skills synonymous with the Army’s and Marine Corps’ military occupation codes (MOS) and Air Force’s Air Force Specialty Code (AFSC). Members who earned high ASVAB scores or who were otherwise guaranteed an “A” School of choice while enlisting may go directly to their “A” School upon graduation from Boot Camp.

Civilian personnel

The Coast Guard employs over 8,577 civilians in over two hundred different job types including Coast Guard Investigative Service special agents, lawyers, engineers, technicians, administrative personnel, tradesmen, and federal firefighters. Civilian employees work at various levels in the Coast Guard to support its various missions.

Equipment

Cutters

The Coast Guard operates 243 cutters, defined as any vessel more than 65 feet (20 m) long, that has a permanently assigned crew and accommodations for the extended support of that crew.

National Security Cutter (WMSL): Also known as the Legend-class, these are the Coast Guard’s latest class of 418-foot (127 m) cutter. At 418 ft. these are the largest USCG military cutters in active service. One-for-one, Legend-class ships have replaced individually decommissioned 1960s Hamilton-class cutters, (also known as the High Endurance Cutter (WHEC)). A total of eleven were authorized and budgeted; as of 2021 eight are in service, and two are under construction.

Medium Endurance Cutter (WMEC): These are mostly the 210-foot (64 m) Reliance-class, and the 270-foot (82 m) Famous-class cutters, although the 283-foot (86 m) Alex Haley also falls into this category. Primary missions are law enforcement, search and rescue, and military defense. Heritage-class cutters are expected to eventually replace the Reliance- and Famous-class cutters as they are completed.

Polar-class icebreaker (WAGB): There are three WAGB’s used for icebreaking and research though only two, the heavy 399-foot (122 m) Polar Star and the newer medium class 420-foot (130 m) Healy, are active.Polar Sea is located in Seattle, Washington but is not currently in active service. The icebreakers are being replaced with new heavy icebreakers under the Polar icebreaker program, the world’s largest coast guard vessel due for delivery in 2025.

USCGC Storis: A 360-foot (110 m) Icebreaker previously used by Royal Dutch Shell before being bought by the Coast Guard in December 2024.

USCGC Eagle: A 295-foot (90 m) sailing barque used as a training ship for Coast Guard Academy cadets and Coast Guard officer candidates. She was originally built in Germany as Horst Wessel, and was seized by the United States as a prize of war in 1945.

USCGC Mackinaw: A 240-foot (73 m) heavy icebreaker built for operations on the Great Lakes.

Seagoing Buoy Tender (WLB): These 225-foot (69 m) ships are used to maintain aids to navigation and also assist with law enforcement and search and rescue.

Coastal Buoy Tender (WLM): The 175-foot (53 m) Keeper-class coastal buoy tenders are used to maintain coastal aids to navigation.

Sentinel-class cutter (WPC): The 154-foot (47 m) Sentinel-class, also known by its program name, the “Fast Response Cutter”-class and is used for search and rescue work and law enforcement.

Bay-class icebreaking tug (WTGB): 140-foot (43 m) icebreakers used primarily for domestic icebreaking missions. Other missions include search and rescue, law enforcement, and aids to navigation maintenance.

Patrol Boats (WPB): There are two classes of WPBs currently in service; the 110-foot (34 m) Island-class patrol boats and the 87-foot (27 m) Marine Protector-class patrol boats

Small Harbor Tug (WYTL): 65-foot (20 m) small icebreaking tugboats, used primary for ice clearing in domestic harbors in addition to limited search and rescue and law enforcement roles.

Boats

The Coast Guard operates about 1,650 boats, defined as any vessel less than 65 feet (20 m) long, which generally operate near shore and on inland waterways.

The Coast Guard boat fleet includes:

47-foot Motor Lifeboat (MLB): The Coast Guard’s 47-foot (14 m) primary heavy-weather boat used for search and rescue as well as law enforcement and homeland security.

Response Boat – Medium (RB-M): A new multi-mission 45-foot (14 m) vessel intended to replace the 41-foot (12 m) utility boat. 170 planned
Deployable Pursuit Boat (DPB): A 38-foot (12 m) launch capable of pursuing fast cocaine smuggling craft.

Long Range Interceptor (LRI): A 36-foot (11 m) high-speed launch that can be launched from the stern ramps of the larger Deepwater cutters.

Aids to Navigation Boat (TANB/BUSL/ATON/ANB): Various designs ranging from 26 to 55 feet (7.9 to 16.8 m) used to maintain aids to navigation.

Special Purpose Craft – Law Enforcement (SPC-LE): Intended to operate in support of specialized law enforcement missions, utilizing three 300 horsepower (220 kW) Mercury Marine engines. The SPC-LE is 33 feet (10 m) long and capable of speeds in excess of 50 knots (93 km/h; 58 mph) and operations more than 30 miles (48 km) from shore.

29-foot Response Boat Small II (RBS-II): The successor to the 25-foot RB-S, the RBS-II is a 29 foot (9 m) high speed, multi-mission boat commonly used for search and rescue, port security, and law enforcement. Improvements from the RB-S include improved visibility and modernized electronic chart plotter capabilities.

25-foot Transportable Port Security Boat (TPSB): A 25-foot (7.6 m) well-armed boat used by Port Security Units for force protection.
Special Purpose Craft, Shallow-water (SPC-SW): 24 feet (7.3 m)

Cutter Boat – Over the Horizon (OTH): A 23-foot (7.0 m) rigid hull inflatable boat used by medium and high endurance cutters and specialized units.

Short Range Prosecutor (SRP): A 23-foot (7.0 m) rigid hull inflatable boat that can be launched from a stern launching ramp on the National Security Cutters.

Aircraft

The Coast Guard operates approximately 201 fixed and rotary wing aircraft from 24 Coast Guard Air Stations throughout the contiguous United States, Alaska, Hawaii, and Puerto Rico. Most of these air stations are tenant activities at civilian airports, several of which are former Air Force Bases and Naval Air Stations, although several are also independent military facilities. Coast Guard Air Stations are also located on active Naval Air Stations, Air National Guard bases, and Army Air Fields.

Coast Guard aviators receive Primary (fixed-wing) and Advanced (fixed or rotary-wing) flight training with their Navy and Marine Corps counterparts at NAS Whiting Field, Florida, and NAS Corpus Christi, Texas, and are considered Naval Aviators. After receiving Naval Aviator Wings, Coast Guard pilots, with the exception of those slated to fly the HC-130, report to U.S. Coast Guard Aviation Training Center, Mobile, Alabama to receive 6–12 weeks of specialized training in the Coast Guard fleet aircraft they will operate. HC-130 pilots report to Little Rock AFB, Arkansas, for joint C-130 training under the auspices of the 314th Airlift Wing of the U.S. Air Force.

Fixed-wing aircraft operate from Air Stations on long-duration missions. Helicopters operate from Air Stations and can deploy on a number of different cutters. Helicopters can rescue people or intercept vessels smuggling migrants or narcotics. Since the terrorist attacks of 11 September 2001, the Coast Guard has developed a more prominent role in national security and now has armed helicopters operating in high-risk areas for the purpose of maritime law enforcement and anti-terrorism.

The Coast Guard is now developing an unmanned aerial vehicle (UAV) program that will utilize the MQ-9 Reaper platform for homeland security and search/rescue operations. To support this endeavor, the Coast Guard has partnered with the Navy and U.S. Customs and Border Protection to study existing/emerging unmanned aerial system (UAS) capabilities within their respective organizations. As these systems mature, research and operational experience gleaned from this joint effort will enable the Coast Guard to develop its own cutter and land-based UAS capabilities.

Weapons

Naval guns

Most Coast Guard Cutters have one or more naval gun systems installed, including:

The Oto Melara 76 mm, a radar-guided computer controlled gun system that is used on Medium Endurance Cutters. The 3-inch gun’s high rate of fire and availability of specialized ammunition make it a multi-purpose gun capable of anti-shipping, anti-aircraft, ground support, and short-range anti-missile defense.
The MK 110 57 mm gun, a radar-guided computer controlled variant of the Bofors 57 mm gun. It is used on the Legend-class cutter, also known as the National Security Cutter (NSC). It is a multi-purpose gun capable of anti-shipping, anti-aircraft, and short-range anti-missile defense. The stealth mount has a reduced radar profile. Also, the gun has a small radar mounted on the gun barrel to measure muzzle velocity for fire control purposes and can change ammunition types instantly due to a dual-feed system. It can also be operated/fired manually using a joystick and video camera (mounted on gun).

The Mk 38 Mod 0 weapons system consists of an M242 Bushmaster 25mm chain gun and the Mk 88 Mod 0 machine gun mount. A manned system, its gyro-stabilization compensates for the pitching deck. It provides ships with defensive and offensive gunfire capability for the engagement of a variety of surface targets. Designed primarily as a close-range defensive measure, it provides protection against patrol boats, floating mines, and various shore-based targets.

The Mk 38 Mod 2 weapons system is a remotely operated Mk 38 with an electronic optical sight, laser range-finder, FLIR, a more reliable feeding system, all of which enhance the weapon systems capabilities and accuracy.

The Phalanx CIWS (pronounced “sea-wiz”) is a close-in weapon system for defense against aircraft and anti-ship missiles. it can also be used against a variety of surface targets. Consisting of a radar-guided 20 mm 6-barreled M61 Vulcan cannon mounted on a swiveling base, it is used on the Coast Guard’s National Security Cutters. This system can operate autonomously against airborne threats or may be manually operated with the use of electronic optical sight, laser range-finder and FLIR systems against surface targets.

The Sea PROTECTOR MK50 is a remotely controlled gyro-stabilized M2 .50 caliber heavy machine gun. The sight package includes a daylight video camera, a thermal camera and an eye-safe laser rangefinder operated by a joystick. It is also furnished with a fully integrated fire control system that provides ballistic correction. The Mk50s are used on only four Marine Protector-class Cutters, the USCGC Sea Fox (WPB-87374), USCGC Sea Devil (WPB-87368), USCGC Sea Dragon (WPB-87367) and USCGC Sea Dog (WPB-87373)

Small arms and light weapons

Colt Gold Match M1911	United States	Semi-automatic pistol	EIC Competition Use
Colt M16A4	United States	Assault rifle	EIC Competition Use
Glock 19 Gen 5 MOS	Austria	Semi-automatic pistol	Standard issue
Remington 870P	United States	Shotgun
Colt M4		Assault rifle
Close Quarters Battle Receiver		Assault rifle
M14 Tactical		Battle rifle
Mk 11 Mod 2 precision rifle		Sniper rifle
Barrett M107 .50-caliber rifle		Sniper rifle	Used by marksmen from the Helicopter Interdiction Tactical Squadron and Law Enforcement Detachments to disable the engines on fleeing boats.
M240 machine gun		General-purpose machine gun	Standard issue

Symbols

Core values

The Coast Guard, like the other armed services of the United States, has a set of core values that serve as basic ethical guidelines for all Coast Guard active duty, reservists, auxiliarists, and civilians. The Coast Guard Core Values are:

Honor: Integrity is our standard. We demonstrate uncompromising ethical conduct and moral behavior in all of our personal actions. We are loyal and accountable to the public trust.

Respect: We value our diverse workforce. We treat each other with fairness, dignity, and compassion. We encourage individual opportunity and growth. We encourage creativity through empowerment. We work as a team.

Devotion to Duty: We are professionals, military and civilian, who seek responsibility, accept accountability, and are committed to the successful achievement of our organizational goals. We exist to serve. We serve with pride.

The Guardian Ethos

In 2008, the Coast Guard introduced the Guardian Ethos. As the commandant, Admiral Allen noted in a message to all members of the Coast Guard: [The Ethos] “defines the essence of the Coast Guard,” and is the “contract the Coast Guard and its members make with the nation and its citizens.”

The Coast Guard Ethos

In an ALCOAST message effective 1 December 2011 the Commandant, Admiral Papp, directed that the language of Guardian Ethos be superseded by the Coast Guard Ethos in an effort to use terminology that would help with the identity of personnel serving in the Coast Guard. The term coast guardsman is the correct form of address used in Title 14 USC and is the form that has been used historically. This changed the line in the Guardian Ethos “I am a Guardian.” to become “I am a Coast Guardsman.”

The Ethos is:

In Service to our Nation
With Honor, Respect, and Devotion to Duty
We protect
We defend
We save
We are Semper Paratus
We are the United States Coast Guard

— The Coast Guard Ethos

Creed of the United States Coast Guardsman

he “Creed of the United States Coast Guardsman” was written by Vice Admiral Harry G. Hamlet, who served as Commandant of the Coast Guard from 1932 to 1936.

I am proud to be a United States Coast Guardsman.
I revere that long line of expert seamen who by their devotion to duty and sacrifice of self have made it possible for me to be a member of a service honored and respected, in peace and in war, throughout the world.
I never, by word or deed, will bring reproach upon the fair name of my service, nor permit others to do so unchallenged.
I will cheerfully and willingly obey all lawful orders.
I will always be on time to relieve, and shall endeavor to do more, rather than less, than my share.
I will always be at my station, alert and attending to my duties.
I shall, so far as I am able, bring to my seniors solutions, not problems.
I shall live joyously, but always with due regard for the rights and privileges of others.
I shall endeavor to be a model citizen in the community in which I live.
I shall sell life dearly to an enemy of my country, but give it freely to rescue those in peril.
With God’s help, I shall endeavor to be one of His noblest Works…
A UNITED STATES COAST GUARDSMAN.

— Creed of the United States Coast Guardsman

“You have to go out, but you don’t have to come back!”

This unofficial motto of the Coast Guard dates to an 1899 United States Lifesaving Service regulation, which states in part: “In attempting a rescue, … he will not desist from his efforts until by actual trial, the impossibility of effecting a rescue is demonstrated. The statement of the keeper that he did not try to use the boat because the sea or surf was too heavy will not be accepted, unless attempts to launch it were actually made and failed.

Coast Guard ensign

The Coast Guard ensign (flag) was first flown by the Revenue Cutter Service in 1799 to distinguish revenue cutters from merchant ships. A 1 August 1799 order issued by Secretary of the Treasury Oliver Wolcott Jr. specified that the Ensign would be “sixteen perpendicular stripes (for the number of states in the United States at the time), alternate red and white, the union of the ensign to be the arms of the United States in a dark blue on a white field.”

This ensign became familiar in American waters and served as the sign of authority for the Revenue Cutter Service until the early 20th century. The ensign was originally intended to be flown only on revenue cutters and boats connected with the Customs Service but over the years it was found flying atop custom houses as well, and the practice became a requirement in 1874. On 7 June 1910, President William Howard Taft issued an executive order adding an emblem to (or “defacing”) the ensign flown by the Revenue cutters to distinguish it from what is now called the Customs Ensign flown from the custom houses. The emblem was changed to the official seal of the Coast Guard in 1927.

The purpose of the ensign is to allow ship captains to easily recognize those vessels having legal authority to stop and board them. It is flown only as a symbol of law enforcement authority and is never carried as a parade standard.

Coast Guard standard

The Coast Guard standard is used in parades and carries the battle honors of the Coast Guard. It was derived from the jack of the Coast Guard ensign which was flown by revenue cutters. The emblem is a blue eagle from the coat of arms of the United States on a white field. Above the eagle are the words “United States Coast Guard” below the eagle is the motto, “Semper Paratus” and the inscription “1790.”

Service Mark (“Racing Stripe”)

The Racing Stripe, officially known as the Service Mark, was designed in 1964 by the industrial design office of Raymond Loewy Associates to give the Coast Guard a distinctive, modern image. Loewy had designed the colors for the Air Force One fleet for Jackie Kennedy. President Kennedy was so impressed with his work, he suggested that the entire Federal Government needed his make-over and suggested that he start with the Coast Guard. The stripes are canted at a 64-degree angle, coincidentally the year the Racing Stripe was designed.

The racing stripe is borne by Coast Guard cutters, aircraft, and many boats. First used and placed into official usage as of 6 April 1967, it consists of a narrow blue stripe, a narrow white stripe between, and a broad CG red bar with the Coast Guard shield centered. Red-hulled icebreaker cutters and most HH-65/MH-65 helicopters (i.e., those with a red fuselage) bear a narrow blue stripe, a narrow empty stripe the color of the fuselage (an implied red stripe), and broad white bar, with the Coast Guard shield centered. Conversely, black-hulled cutters (such as buoy tenders and inland construction tenders) use the standard racing stripe. Auxiliary vessels maintained by the Coast Guard also carry the Racing Stripe, but in inverted colors (i.e., broad blue stripe with narrow white and CG red stripes) and the Auxiliary shield. Similar racing stripe designs have been adopted for the use of other coast guards and maritime authorities and many other law enforcement and rescue agencies.

Uniforms

For most of the Coast Guard’s history, its uniforms largely mirrored the style of U.S. Navy uniforms, distinguishable only by their insignia. In 1974, under the leadership of Admiral Chester R. Bender, the initial versions of the current Coast Guard Service Dress Blue and Tropical uniforms were introduced. This represented a major departure from many common conventions in naval and maritime uniforms. Notably, “Bender’s Blues” was a common service dress uniform for all ranks, dispensing with the sailor suit and sailor cap formerly worn by enlisted members. Rank insignia remained consistent with the naval pattern and some distinctly-nautical items such as the pea coat, officer’s sword, and dress white uniforms remained.

Today, the Coast Guard’s uniforms remain among the simplest of any branch of the armed forces, with fewer total uniforms and uniform variants than the other armed services. There are only three uniforms that typically serve as standard uniforms of the day—the Operational Dress Uniform, Tropical Blue, and Service Dress Blue (Bravo).

Coast Guard Reserve

The United States Coast Guard Reserve is the reserve military force of the Coast Guard. The Coast Guard Reserve was founded on 19 February 1941. The Coast Guard has 8700 reservists who normally drill two days a month and an additional 12 days of active duty each year, although many perform additional drill and active duty periods, to include those mobilized to extended active duty. Coast Guard reservists possess the same training and qualifications as their active duty counterparts, and as such, can be found augmenting active duty Coast Guard units every day.

During the Vietnam War and shortly thereafter, the Coast Guard considered abandoning the reserve program, but the force was instead reoriented into force augmentation, where its principal focus was not just reserve operations, but to add to the readiness and mission execution of every-day active duty personnel.

Since 11 September 2001, reservists have been activated and served on tours of active duty, to include deployments to the Persian Gulf and also as parts of Department of Defense combatant commands such as the U.S. Northern and Central Commands. Coast Guard Port Security Units are entirely staffed with reservists, except for five to seven active duty personnel. Additionally, most of the staffing the Coast Guard provides to the Navy Expeditionary Combat Command are reservists.

The Reserve is managed by the Assistant Commandant for Reserve, Rear Admiral James M. Kelly, USCG.

Women in the Coast Guard

There have been women in the United States Coast Guard since 1918, and women continue to serve in it today.

During World War I, in January 1918, radio and telegraph operator Myrtle Hazard enlisted as an electrician. She was the only woman to serve during the war and she is the namesake of USCGC Myrtle Hazard . While some newspapers reported that twin sisters Genevieve and Lucille Baker were the first women to serve in the Coast Guard, their attempt to enlist was rejected.

Coast Guard Auxiliary

The United States Coast Guard Auxiliary is the uniformed, civilian volunteer component of the United States Coast Guard, created on 23 June 1939 by an act of Congress. Although it is a civilian organization, it was originally named the “United States Coast Guard Reserve” and was later re-named the “United States Coast Guard Auxiliary” on 19 February 1941 when a military reserve force for the Coast Guard was created. As part of “Team Coast Guard” (the term used to collectively describe all active, reserve, auxiliary, and civilian employees), the auxiliary carries out, or assists in, nearly all of the Coast Guard’s noncombatant and non-law enforcement missions. Auxiliarists are subject to direction from the commandant of the Coast Guard. As of 2022, there were approximately 26,000 members of the U.S. Coast Guard Auxiliary.

Coast Guard policy has assigned many of its duties related to recreational boating safety to the Auxiliary, including public boating safety education and outreach. This includes offering boating skills courses, liaising with marine-related businesses at the local level, and providing voluntary Vessel Safety Checks (formerly called Courtesy Examinations) to the public. Additionally, Auxiliarists use their own vessels, boats, and aircraft (once registered as Coast Guard facilities) to provide operational support to the Coast Guard by conducting safety patrols, assisting in search and rescue missions, inspecting aids to navigation, and performing other tasks on behalf of the Coast Guard.

Prior to 1997, Auxiliarists were largely limited to activities supporting recreational boating safety. In 1997, however, new legislation authorized the Auxiliary to participate in any and all Coast Guard missions except direct military and direct law enforcement. Auxiliarists may directly augment active duty Coast Guard personnel in non-combat, non-law enforcement roles (e.g. radio communications watch stander, interpreter, cook, etc.) and may assist active duty personnel in inspecting commercial vessels and maintaining aids-to-navigation. Auxiliarists may support the law enforcement and homeland security missions of the Coast Guard but may not directly participate (make arrests, etc.), and Auxiliarists are not permitted to carry a weapon while serving in any Auxiliary capacity.

Medals and honors

One coast guardsman, Douglas Albert Munro, has earned the Medal of Honor, the highest military award of the United States. Fifty-five coast guardsmen have earned the Navy Cross and numerous men and women have earned the Distinguished Flying Cross.

The highest peacetime decoration awarded within the Coast Guard is the Homeland Security Distinguished Service Medal; prior to the transfer of the Coast Guard to the Department of Homeland Security, the highest peacetime decoration was the Department of Transportation Distinguished Service Medal. The highest unit award available is the Presidential Unit Citation.

In wartime, members of the Coast Guard are eligible to receive the Navy version of the Medal of Honor. A Coast Guard Medal of Honor is authorized but has not yet been developed or issued.

In May 2006, at the Change of Command ceremony when Admiral Thad Allen took over as Commandant, President George W. Bush awarded the entire Coast Guard, including the Coast Guard Auxiliary, the Coast Guard Presidential Unit Citation with hurricane device, for its efforts during and after Hurricane Katrina and Tropical Storm Rita.

Notable coast guardsmen

Numerous celebrities have served in the Coast Guard including tennis player Jack Kramer, golfer Arnold Palmer, All Star baseball player Sid Gordon, boxer Jack Dempsey; surfer and inventor Tom Blake; musicians Kai Winding, Rudy Vallee, Derroll Adams, and Tom Waits; actors Buddy Ebsen, Sid Caesar, Victor Mature, Richard Cromwell, Alan Hale Jr., William Hopper, Beau Bridges, Jeff Bridges, Cesar Romero; author Alex Haley; and Senator Claiborne Pell.

Vice Admiral Thad Allen in 2005 was named Principal Federal Officer to oversee recovery efforts in the Gulf Region after Hurricane Katrina. After promotion to Admiral, on the eve of his retirement as Commandant, Allen again received national visibility after being named National Incident Commander overseeing the response efforts of the Deepwater Horizon oil spill.

Former Coast Guard officers have been appointed to numerous civilian government offices. After retiring as Commandant of the Coast Guard in 2002, Admiral James Loy went on to serve as United States deputy secretary of homeland security. After their respective Coast Guard careers, Carlton Skinner served as the first civilian governor of Guam; G. William Miller, 65th secretary of the treasury, and retired vice admiral Harvey E. Johnson Jr. served as Deputy Administrator and Chief Operating Officer of the Federal Emergency Management Agency (FEMA) under President George W. Bush. Rear Admiral Stephen W. Rochon was appointed by President George W. Bush to serve as the director of the executive residence and White House chief usher, beginning service on 12 March 2007, and continued to serve in the same capacity under President Barack Obama.

Two Coast Guard aviators, Commander Bruce E. Melnick and Captain Daniel C. Burbank, have served as NASA astronauts. Coast Guard Reserve commander Andre Douglas was selected in 2021 to join NASA Astronaut Group 23.

Signalman First Class Douglas Albert Munro was awarded the Medal of Honor posthumously, and is the only coast guardsman to ever receive this honor.

Organizations

Coast Guard Aviation Association

Those who have piloted or flown in Coast Guard aircraft under official flight orders may join the Coast Guard Aviation Association which was formerly known as the “Ancient Order of the Pterodactyl” (“Flying Since the World was Flat”). The Ancient Albatross Award is presented to the active duty USCG member who qualified as an aviator earlier than any other person who is still serving. Separate enlisted and officer awards are given.

Coast Guard CW Operators Association

The Coast Guard CW Operators Association (CGCWOA) is a membership organization comprising primarily former members of the United States Coast Guard who held the enlisted rating of Radioman (RM) or Telecommunications Specialist (TC), and who employed International Morse Code (CW) in their routine communications duties on Coast Guard cutters and at shore stations.

USCG Chief Petty Officers Association

Members of this organization unite to assist members and dependents in need, assist with Coast Guard recruiting efforts, support the aims and goals of the Coast Guard Chief Petty Officers Academy, keep informed on Coast Guard matters, and assemble for social amenities; and include Chief, Senior Chief, and Master Chief Petty Officers, active, reserve and retired. Membership is also open to all Chief Warrant Officers and Officers who have served as a Chief Petty Officer.

USCG Chief Warrant and Warrant Officers Association (CWOA)

Established in 1929, the Chief Warrant and Warrant Officers Association, United States Coast Guard (CWOA) represents Coast Guard warrant and chief warrant officers (active, reserve and retired) to the Congress, White House and the Department of Homeland Security. Additionally, the association communicates with the Coast Guard leadership on matters of concern to Coast Guard chief warrant officers.

In popular culture

The U.S. Coast Guard maintains a Motion Picture and Television Office (MOPIC) in Hollywood, California, along with its sister services at the Department of Defense dedicated to enhancing public awareness and understanding of the Coast Guard, its people, and its missions through a cooperative effort with the entertainment industry.

March 24, 2025

United States Marine Corps

The United States Marine Corps (USMC), also referred to as the United States Marines or simply the Marines, is the maritime land force service branch of the United States Department of Defense. It is responsible for conducting expeditionary and amphibious operations through combined arms, implementing its own infantry, artillery, aerial, and special operations forces. The U.S. Marine Corps is one of the six armed forces of the United States and one of the eight uniformed services of the United States.

The Marine Corps has been part of the United States Department of the Navy since 30 June 1834 with its sister service, the United States Navy. The USMC operates installations on land and aboard sea-going amphibious warfare ships around the world. Additionally, several of the Marines’ tactical aviation squadrons, primarily Marine Fighter Attack squadrons, are also embedded in Navy carrier air wings and operate from the aircraft carriers.

The history of the Marine Corps began when two battalions of Continental Marines were formed on 10 November 1775 in Philadelphia as a service branch of infantry troops capable of fighting both at sea and on shore. In the Pacific theater of World War II, the Corps took the lead in a massive campaign of amphibious warfare, advancing from island to island. As of December 2024, the USMC has around 169,000 active duty members and some 33,000 personnel in reserve.

Mission

The Marine Band, dubbed the “President’s Own” by John Adams, provides music for state functions at the White House. Marines from Ceremonial Companies A & B, quartered in Marine Barracks, Washington, D.C., guard presidential retreats, including Camp David, and the marines of the Executive Flight Detachment of HMX-1 provide helicopter transport to the president and vice president, with the radio call signs “Marine One” and “Marine Two”, respectively. The Executive Flight Detachment also provides helicopter transport to Cabinet members and other VIPs. By authority of the 1946 Foreign Service Act, the Marine Security Guard of the Marine Embassy Security Command provide security for American embassies, legations, and consulates at more than 140 posts worldwide.

The relationship between the Department of State and the U.S. Marine Corps is nearly as old as the Corps itself. For over 200 years, Marines have served at the request of various secretaries of state. After World War II, an alert, disciplined force was needed to protect American embassies, consulates, and legations throughout the world. In 1947, a proposal was made that the Department of Defense furnish Marine Corps personnel for Foreign Service guard duty under the provisions of the Foreign Service Act of 1946. A formal Memorandum of Agreement was signed between the Department of State and the secretary of the Navy on 15 December 1948, and 83 Marines were deployed to overseas missions. During the first year of the program, 36 detachments were deployed worldwide.

Historical mission

As outlined in 10 U.S.C. § 5063 and as originally introduced under the National Security Act of 1947, the three primary areas of responsibility for the U.S. Marine Corps are:

Seizure or defense of advanced naval bases and other land operations to support naval campaigns;
Development of tactics, technique, and equipment used by amphibious landing forces in coordination with the Army and Air Force; and
Such other duties as the president or Department of Defense may direct.
This last clause derives from similar language in the congressional acts “For the Better Organization of the Marine Corps” of 1834 and “Establishing and Organizing a Marine Corps” of 1798. In 1951, the House of Representatives’ Armed Services Committee called the clause “one of the most important statutory – and traditional – functions of the Marine Corps”. It noted that the Corps has more often than not performed actions of a non-naval nature, including its famous actions in Tripoli, the War of 1812, Chapultepec, and numerous counterinsurgency and occupational duties (such as those in Central America, World War I, and the Korean War). While these actions are not accurately described as support of naval campaigns nor as amphibious warfare, their common thread is that they are of an expeditionary nature, using the mobility of the Navy to provide timely intervention in foreign affairs on behalf of American interests.

The Marine Corps was founded to serve as an infantry unit aboard naval vessels and was responsible for the security of the ship and its crew by conducting offensive and defensive combat during boarding actions and defending the ship’s officers from mutiny; to the latter end, their quarters on the ship were often strategically positioned between the officers’ quarters and the rest of the vessel. Continental Marines manned raiding parties, both at sea and ashore. America’s first amphibious assault landing occurred early in the Revolutionary War, on 3 March 1776, as the Marines gained control of Fort Montagu and Fort Nassau, a British ammunition depot and naval port in New Providence, the Bahamas. The role of the Marine Corps has expanded significantly since then; as the importance of its original naval mission declined with changing naval warfare doctrine and the professionalization of the naval service, the Corps adapted by focusing on formerly secondary missions ashore. The Advanced Base Doctrine of the early 20th century codified their combat duties ashore, outlining the use of Marines in the seizure of bases and other duties on land to support naval campaigns. In 1987, the USMC Sea School was closed; in 1998, all Marine Detachments on board ships were disbanded.

Throughout the late 19th and 20th centuries, Marine detachments served aboard Navy cruisers, battleships, and aircraft carriers. Marine detachments served in their traditional duties as a ship’s landing force, manning the ship’s weapons and providing shipboard security. Marine detachments were augmented by members of the ship’s company for landing parties, such as in the First Sumatran expedition of 1832 and continuing in the Caribbean and Mexican campaigns of the early 20th centuries. Marines developed tactics and techniques of amphibious assault on defended coastlines in time for use in World War II. During World War II, Marines continued to serve on capital ships, and some were assigned to man anti-aircraft batteries.

In 1950, President Harry Truman responded to a message from U.S. representative Gordon L. McDonough. McDonough had urged President Truman to add Marine representation on the Joint Chiefs of Staff. President Truman, writing in a letter addressed to McDonough, stated, “The Marine Corps is the Navy’s police force and as long as I am President that is what it will remain. They have a propaganda machine that is almost equal to Stalin’s.” McDonough then inserted President Truman’s letter, dated 29 August 1950, into the Congressional Record. Congressmen and Marine organizations reacted, calling President Truman’s remarks an insult, and demanded an apology. Truman apologized to the Marine commandant at the time, writing, “I sincerely regret the unfortunate choice of language which I used in my letter of August 29 to Congressman McDonough concerning the Marine Corps.” While Truman had apologized for his metaphor, he did not alter his position that the Marine Corps should continue to report to the Navy secretary. He made amends only by making a surprise visit to the Marine Corps League a few days later, when he reiterated, “When I make a mistake, I try to correct it. I try to make as few as possible.” He received a standing ovation.

When gun cruisers were retired by the end of the 1970s, the remaining Marine detachments were only seen on battleships and carriers. Its original mission of providing shipboard security ended in the 1990s.

Capabilities

The Marine Corps fulfills a critical military role as an amphibious warfare force. It is capable of asymmetric warfare with conventional, irregular, and hybrid forces. While the Marine Corps does not employ any unique capabilities, as a force, it can rapidly deploy a combined-arms task force to almost anywhere in the world within days. The basic structure for all deployed units is a Marine Air-Ground Task Force (MAGTF) that integrates a ground combat element, an aviation combat element, and a logistics combat element under a common command element. While the creation of joint commands under the Goldwater–Nichols Act has improved interservice coordination between each branch, the Corps’s ability to permanently maintain integrated multielement task forces under a single command provides a smoother implementation of combined-arms warfare principles.

The close integration of disparate Marine units stems from an organizational culture centered on the infantry. Every other Marine capability exists to support the infantry. Unlike some Western militaries, the Corps remained conservative against theories proclaiming the ability of new weapons to win wars independently. For example, Marine aviation has always been focused on close air support and has remained largely uninfluenced by air power theories proclaiming that strategic bombing can single-handedly win wars.

This focus on the infantry is matched with the doctrine of “Every Marine [is] a rifleman”, a precept of Commandant Alfred M. Gray, Jr., emphasizing the infantry combat abilities of every Marine. All Marines, regardless of military specialization, receive training as a rifleman, and all officers receive additional training as infantry platoon commanders. During World War II at the Battle of Wake Island, when all the Marine aircraft were destroyed, pilots continued the fight as ground officers, leading supply clerks and cooks in a final defensive effort.Flexibility of execution is implemented via an emphasis on “commander’s intent” as a guiding principle for carrying out orders, specifying the end state but leaving open the method of execution.

The amphibious assault techniques developed for World War II evolved, with the addition of air assault and maneuver warfare doctrine, into the current “Operational Maneuver from the Sea” doctrine of power projection from the seas. The Marines are credited with developing helicopter insertion doctrine and were the earliest in the American military to widely adopt maneuver-warfare principles, which emphasize low-level initiative and flexible execution. In light of recent warfare that has strayed from the Corps’s traditional missions, the Marines have renewed an emphasis on amphibious capabilities.

The Marine Corps relies on the Navy for sealift to provide its rapid deployment capabilities. In addition to basing a third of the Fleet Marine Force in Japan, Marine expeditionary units (MEU) are typically stationed at sea so they can function as first responders to international incidents. To aid rapid deployment, the Maritime Pre-Positioning System was developed: Fleets of container ships are positioned throughout the world with enough equipment and supplies for a marine expeditionary force to deploy for 30 days.

Doctrine

Two small manuals published during the 1930s established USMC doctrine in two areas. The Small Wars Manual laid the framework for Marine counterinsurgency operations from Vietnam to Iraq and Afghanistan while the Tentative Landing Operations Manual established the doctrine for the amphibious operations of World War II. “Operational Maneuver from the Sea” was the doctrine of power projection in 2006.

History

Foundation and American Revolutionary War

The United States Marine Corps traces its roots to the Continental Marines of the American Revolutionary War, formed by Captain Samuel Nicholas by a resolution of the Second Continental Congress on 10 November 1775, to raise two battalions of marines. This date is celebrated as the birthday of the Marine Corps. Nicholas was nominated to lead the Marines by John Adams. By December 1775, Nicholas raised one battalion of 300 men by recruitment in his home city of Philadelphia.

In January 1776, the Marines went to sea under the command of Commodore Esek Hopkins and in March undertook their first amphibious landing, the Battle of Nassau in the Bahamas, occupying the British port of Nassau for two weeks. On 3 January 1777, the Marines arrived at the Battle of Princeton attached to General John Cadwalader’s brigade, where they had been assigned by General George Washington; by December 1776, Washington was retreating through New Jersey and, needing veteran soldiers, ordered Nicholas and the Marines to attach themselves to the Continental Army. The Battle of Princeton, where the Marines along with Cadwalader’s brigade were personally rallied by Washington, was the first land combat engagement of the Marines; an estimated 130 marines were present at the battle.

At the end of the American Revolution, both the Continental Navy and Continental Marines were disbanded in April 1783. The institution was resurrected on 11 July 1798; in preparation for the Quasi-War with France, Congress created the United States Marine Corps. Marines had been enlisted by the War Department as early as August 1797 for service in the newly-built frigates authorized by the Congressional “Act to provide a Naval Armament” of 18 March 1794, which specified the numbers of marines to recruit for each frigate.

The Marines’ most famous action of this period occurred during the First Barbary War (1801–1805) against the Barbary pirates, when William Eaton and First Lieutenant Presley O’Bannon led 8 marines and 500 mercenaries in an effort to capture Tripoli. Though they only reached Derna, the action at Tripoli has been immortalized in the Marines’ Hymn and the Mameluke sword carried by Marine officers.

War of 1812 and afterward

During the War of 1812, Marine detachments on Navy ships took part in some of the great frigate duels that characterized the war, which were the first and last engagements of the conflict. Their most significant contribution was holding the center of General Andrew Jackson’s defensive line at the 1815 Battle of New Orleans, the final major battle and one of the most one-sided engagements of the war. With widespread news of the battle and the capture of HMS Cyane, HMS Levant and HMS Penguin, the final engagements between British and U.S. forces, the Marines had gained a reputation as expert marksmen, especially in defensive and ship-to-ship actions. They played a large role in the 1813 defense of Sacket’s Harbor, New York and Norfolk and Portsmouth, Virginia, also taking part in the 1814 defense of Plattsburgh in the Champlain Valley during one of the final British offensives along the Canadian–U.S. border. The Battle of Bladensburg, fought 24 August 1814, was one of the worst days for American arms, though a few units and individuals performed heroic service. Notable among them were Commodore Joshua Barney’s 500 sailors and the 120 marines under Captain Samuel Miller USMC, who inflicted the bulk of British casualties and were the only effective American resistance during the battle. A final desperate Marine counter attack, with the fighting at close quarters, however was not enough; Barney and Miller’s forces were overrun. In all of 114 marines, 11 were killed and 16 wounded. During the battle Captain Miller’s arm was badly wounded, for his gallant service in action, Miller was brevetted to the rank of Major USMC.

After the war, the Marine Corps fell into a malaise that ended with the appointment of Archibald Henderson as its fifth commandant in 1820. Under his tenure, the Corps took on expeditionary duties in the Caribbean, the Gulf of Mexico, Key West, West Africa, the Falkland Islands, and Sumatra. Commandant Henderson is credited with thwarting President Jackson’s attempts to combine and integrate the Marine Corps with the Army. Instead, Congress passed the Act for the Better Organization of the Marine Corps in 1834, stipulating that the Corps was part of the Department of the Navy as a sister service to the Navy.

Commandant Henderson volunteered the Marines for service in the Seminole Wars of 1835, personally leading nearly half of the entire Corps (two battalions) to war. A decade later, in the Mexican–American War (1846–1848), the Marines made their famed assault on Chapultepec Palace in Mexico City, which would be later celebrated as the “Halls of Montezuma” in the Marines’ Hymn. In fairness to the U.S. Army, most of the troops who made the final assault at the Halls of Montezuma were soldiers and not Marines. The Americans forces were led by Army General Winfield Scott. Scott organized two storming parties of about 250 men each for 500 men total including 40 marines.

In the 1850s, the Marines engaged in service in Panama and Asia and were attached to Commodore Matthew Perry’s East India Squadron on its historic trip to the Far East.

American Civil War to World War I

The Marine Corps played a small role in the Civil War (1861–1865); their most prominent task was blockade duty. As more and more states seceded from the Union, about a third of the Corps’s officers left the United States to join the Confederacy and form the Confederate States Marine Corps, which ultimately played little part in the war. The battalion of recruits formed for the First Battle of Bull Run performed poorly, retreating with the rest of the Union forces. Blockade duty included sea-based amphibious operations to secure forward bases. In early November 1861, a group of sailors and Marines landed in the towns of Port Royal and Beaufort, South Carolina. A few days later that task force captured nearby Hilton Head Island. A couple of weeks later a reconnaissance in force group captured Tybee Island. This is where the Union set up the artillery barrage to bombard Fort Pulaski. In April and May 1862, Marines participated in the capture and occupation of New Orleans and the occupation of Baton Rouge, Louisiana, key events in the war that helped secure Union control of the lower Mississippi River basin and denied the Confederacy a major port and naval base on the Gulf Coast.

The remainder of the 19th century was marked by declining strength and introspection about the mission of the Marine Corps. The Navy’s transition from sail to steam put into question the need for Marines on naval ships. Meanwhile, Marines served as a convenient resource for interventions and landings to protect American interests overseas. The Corps was involved in over 28 separate interventions in the 30 years from the end of the American Civil War to the end of the 19th century. They were called upon to stem political and labor unrest within the United States. Under Commandant Jacob Zeilin’s tenure, Marine customs and traditions took shape: the Corps adopted the Marine Corps emblem on 19 November 1868. It was during this time that “The Marines’ Hymn” was first heard. Around 1883, the Marines adopted their current motto “Semper fidelis” (Always Faithful). John Philip Sousa, the musician and composer, enlisted as a Marine apprentice at age 13, serving from 1867 until 1872, and again from 1880 to 1892 as the leader of the Marine Band.

During the Spanish–American War (1898), Marines led American forces ashore in the Philippines, Cuba, and Puerto Rico, demonstrating their readiness for deployment. At Guantánamo Bay, Cuba, the Marines seized an advanced naval base that remains in use today. Between 1899 and 1916, the Corps continued its record of participation in foreign expeditions, including the Philippine–American War, the Boxer Rebellion in China, Panama, the Cuban Pacifications, the Perdicaris incident in Morocco, Veracruz, Santo Domingo, and the Banana Wars in Haiti and Nicaragua;[citation needed] the experiences gained in counterinsurgency and guerrilla operations during this period were consolidated into the Small Wars Manual.

World War I

During World War I, Marines served as a part of the American Expeditionary Force under General John J. Pershing when America entered into the war on 6 April 1917. The Marine Corps had a deep pool of officers and non-commissioned officers with battle experience and thus experienced a large expansion. The U.S. Marine Corps entered the war with 511 officers and 13,214 enlisted personnel and by 11 November 1918 had reached a strength of 2,400 officers and 70,000 enlisted. African-Americans were entirely excluded from the Marine Corps during this conflict. Opha May Johnson was the first woman to enlist in the Marines; she joined the Marine Corps Reserve in 1918 during World War I, officially becoming the first female Marine. From then until the end of World War I, 305 women enlisted in the Corps. During the Battle of Belleau Wood in 1918, the Marines and U.S. media reported that Germans had nicknamed them Teufel Hunden, meaning “Devil Dogs” for their reputation as shock troops and marksmen at ranges up to 900 meters; there is no evidence of this in German records (as Teufelshunde would be the proper German phrase). Nevertheless, the name stuck in U.S. Marine lore.

Between the World Wars, the Marine Corps was headed by Commandant John A. Lejeune, and under his leadership, the Corps studied and developed amphibious techniques that would be of great use in World War II. Many officers, including Lieutenant Colonel Earl Hancock “Pete” Ellis, foresaw a war in the Pacific with Japan and undertook preparations for such a conflict. Through 1941, as the prospect of war grew, the Corps pushed urgently for joint amphibious exercises with the Army and acquired amphibious equipment that would prove of great use in the upcoming conflict.

World War II

In World War II, the Marines performed a central role in the Pacific War, along with the U.S. Army. The battles of Guadalcanal, Bougainville, Tarawa, Guam, Tinian, Cape Gloucester, Saipan, Peleliu, Iwo Jima, and Okinawa saw fierce fighting between marines and the Imperial Japanese Army. Some 600,000 Americans served in the U.S. Marine Corps in World War II.

The Battle of Iwo Jima, which began on 19 February 1945, was arguably the most famous Marine engagement of the war. The Japanese had learned from their defeats in the Marianas Campaign and prepared many fortified positions on the island including pillboxes and network of tunnels. The Japanese put up fierce resistance, but American forces reached the summit of Mount Suribachi on 23 February. The mission was accomplished with high losses of 26,000 American casualties and 22,000 Japanese.

The Marines played a comparatively minor role in the European theater. Nonetheless, they did continue to provide security detachments to U.S. embassies and ships, contributed personnel to small special ops teams dropped into Nazi-occupied Europe as part of Office of Strategic Services (OSS, the precursor to the CIA) missions, and acted as staff planners and trainers for U.S. Army amphibious operations, including the Normandy landings.

By the end of the war, the Corps had expanded from two brigades to six divisions, five air wings, and supporting troops, totaling about 485,000 marines. In addition, 20 defense battalions and a parachute battalion were raised.Nearly 87,000 marines were casualties during World War II (including nearly 20,000 killed), and 82 were awarded the Medal of Honor.

In 1942, the Navy Seabees were created with the Marine Corps providing their organization and military training. Many Seabee units were issued the USMC standard issue and were re-designated “Marine”. Despite the Corps giving them their military organization and military training, issuing them uniforms, and redesignating their units, the Seabees remained Navy. USMC historian Gordon L. Rottmann writes that one of the “Navy’s biggest contributions to the Marine Corps during WWII was the creation of the Seabees.”

Despite Secretary of the Navy James Forrestal’s prediction that the Marine flag raising at Iwo Jima meant “a Marine Corps for the next five hundred years”, the Corps faced an immediate institutional crisis following the war because of a suddenly shrunken budget. Army generals pushing for a strengthened and reorganized defense establishment attempted to fold the Marine mission and assets into the Navy and Army. Drawing on hastily assembled Congressional support, and with the assistance of the so-called “Revolt of the Admirals”, the Marine Corps rebuffed such efforts to dismantle the Corps, resulting in statutory protection of the Marine Corps in the National Security Act of 1947. Shortly afterward, in 1952 the Douglas–Mansfield Act afforded the commandant an equal voice with the Joint Chiefs of Staff on matters relating to the Marines and established the structure of three active divisions and air wings that remain today.

Korean War

The beginning of the Korean War (1950–1953) saw the hastily formed Provisional Marine Brigade holding the defensive line at the Pusan Perimeter. To execute a flanking maneuver, General Douglas MacArthur called on United Nations forces, including U.S. Marines, to make an amphibious landing at Inchon. The successful landing resulted in the collapse of North Korean lines and the pursuit of North Korean forces north near the Yalu River until the entrance of the People’s Republic of China into the war. Chinese troops surrounded, surprised, and overwhelmed the overextended and outnumbered American forces. The U.S. Army’s X Corps, which included the 1st Marine Division and the Army’s 7th Infantry Division regrouped and inflicted heavy casualties during their fighting withdrawal to the coast, known as the Battle of Chosin Reservoir.

The fighting calmed after the Battle of the Chosin Reservoir, but late in March 1953, the relative quiet of the war was broken when the People’s Liberation Army launched a massive offensive on three outposts manned by the 5th Marine Regiment. These outposts were codenamed “Reno”, “Vegas”, and “Carson”. The campaign was collectively known as the Nevada Cities Campaign. There was brutal fighting on Reno Hill, which was eventually captured by the Chinese. Although Reno was lost, the 5th Marines held both Vegas and Carson through the rest of the campaign. In this one campaign, the Marines suffered approximately 1,000 casualties and might have suffered much more without the U.S. Army’s Task Force Faith. Marines would continue a battle of attrition around the 38th Parallel until the 1953 armistice. During the war, the Corps expanded from 75,000 regulars to a force of 261,000 marines, mostly reservists; 30,544 marines were killed or wounded during the war, and 42 were awarded the Medal of Honor.

Vietnam War

The Marine Corps served in the Vietnam War, taking part in such battles as the Battle of Hue and the Battle of Khe Sanh in 1968. Individuals from the USMC generally operated in the Northern I Corps Regions of South Vietnam. While there, they were constantly engaged in a guerrilla war against the Viet Cong, along with an intermittent conventional war against the North Vietnamese Army, this made the Marine Corps known throughout Vietnam and gained a frightening reputation from the Viet Cong. Portions of the Corps were responsible for the less-known Combined Action Program that implemented unconventional techniques for counterinsurgency and worked as military advisors to the Republic of Vietnam Marine Corps. Marines were withdrawn in 1971 and returned briefly in 1975 to evacuate Saigon and attempt a rescue of the crew of the SS Mayaguez. Vietnam was the longest war up to that time for the Marines; by its end, 13,091 had been killed in action,51,392 had been wounded, and 57 Medals of Honor had been awarded. Because of policies concerning rotation, more marines were deployed for service during Vietnam than World War II.

While recovering from Vietnam, the Corps hit a detrimental low point in its service history caused by courts-martial and non-judicial punishments related partially to increased unauthorized absences and desertions during the war. Overhaul of the Corps began in the late 1970s, discharging the most delinquent, and once the quality of new recruits improved, the Corps focused on reforming the non-commissioned officer Corps, a vital functioning part of its forces.

Interim: Vietnam War to the War on Terror

After the Vietnam War, the U.S. Marines resumed their expeditionary role, participating in the failed 1980 Iran hostage rescue attempt Operation Eagle Claw, the Operation Urgent Fury and the Operation Just Cause. On 23 October 1983, the Marine barracks in Beirut was bombed, causing the highest peacetime losses to the Corps in its history (220 marines and 21 other service members were killed) and leading to the American withdrawal from Lebanon. In 1990, Marines of the Joint Task Force Sharp Edge saved thousands of lives by evacuating British, French and American nationals from the violence of the Liberian Civil War.

During the Persian Gulf War of 1990 to 1991, Marine task forces formed for Operation Desert Shield and later liberated Kuwait, along with Coalition forces, in Operation Desert Storm. Marines participated in combat operations in Somalia (1992–1995) during Operations Restore Hope, Restore Hope II, and United Shield to provide humanitarian relief.In 1997, Marines took part in Operation Silver Wake, the evacuation of American citizens from the U.S. embassy in Tirana, Albania.

Global War on Terrorism

Following the attacks on 11 September 2001, President George W. Bush announced the Global War on Terrorism. The stated objective of the Global War on Terror is “the defeat of Al-Qaeda, other terrorist groups and any nation that supports or harbors terrorists”. Since then, the Marine Corps, alongside the other military services, has engaged in global operations around the world in support of that mission.

In spring 2009, President Barack Obama’s goal of reducing spending in the Defense Department was led by Secretary Robert Gates in a series of budget cuts that did not significantly change the Corps’s budget and programs, cutting only the VH-71 Kestrel and resetting the VXX program.However, the National Commission on Fiscal Responsibility and Reform singled the Corps out for the brunt of a series of recommended cuts in late 2010. In light of budget sequestration in 2013, General James Amos set a goal of a force of 174,000 Marines. He testified that this was the minimum number that would allow for an effective response to even a single contingency operation, but it would reduce the peacetime ratio of time at home bases to time deployed down to a historical low level.

Afghanistan Campaign

Marines and other American forces began staging in Pakistan and Uzbekistan on the border of Afghanistan as early as October 2001 in preparation for Operation Enduring Freedom. The 15th and 26th Marine Expeditionary Units were some of the first conventional forces into Afghanistan in support of Operation Enduring Freedom in November 2001.

After that, Marine battalions and squadrons rotated through, engaging the Taliban and Al-Qaeda forces. Marines of the 24th Marine Expeditionary Unit flooded into the Taliban-held town of Garmsir in Helmand Province on 29 April 2008, in the first major American operation in the region in years. In June 2009, 7,000 marines with the 2nd Marine Expeditionary Brigade (2nd MEB) deployed to Afghanistan in an effort to improve security and began Operation Strike of the Sword the next month. In February 2010, the 2nd MEB launched the largest offensive of the Afghan Campaign since 2001, the Battle of Marjah, to clear the Taliban from their key stronghold in Helmand Province. After Marjah, marines progressed north up the Helmand River and cleared the towns of Kajahki and Sangin. Marines remained in Helmand Province until 2014.

Iraq Campaign

U.S. marines served in the Iraq War, along with its sister services. The I Marine Expeditionary Force, along with the U.S. Army’s 3rd Infantry Division, spearheaded the 2003 invasion of Iraq. The marines left Iraq in the summer of 2003 but returned in the beginning of 2004. They were given responsibility for the Al Anbar Province, the large desert region to the west of Baghdad. During this occupation, the Marines lead assaults on the city of Fallujah in April (Operation Vigilant Resolve) and November 2004 (Operation Phantom Fury) and saw intense fighting in such places as Ramadi, Al-Qa’im and Hīt. The service’s time in Iraq courted controversy with events such as the Haditha killings and the Hamdania incident. The Anbar Awakening and 2007 surge reduced levels of violence. The Marine Corps officially ended its role in Iraq on 23 January 2010 when it handed over responsibility for Al Anbar Province to the U.S. Army. Marines returned to Iraq in the summer of 2014 in response to growing violence there.

Operations in Africa

Throughout the Global War on Terrorism, the U.S. Marines have supported operations in Africa to counter Islamic extremism and piracy in the Red Sea. In late 2002, Combined Joint Task Force – Horn of Africa was stood up at Camp Lemonnier, Djibouti to provide regional security. Despite transferring overall command to the Navy in 2006, the Marines continued to operate in the Horn of Africa into 2007.

Reshaped for China threat

In the 2020s, as the U.S. national strategy shifted from the war on terrorism to competition with China, the Marine Corps abandoned its previous plan to focus on land operations and strengthened its firepower configuration in the Indo-Pacific region to defeat the Chinese People’s Liberation Army in possible island operations. As part of this shift the USMC has established a joint deployment with the Australian military in Darwin starting with 200 Marines in 2011.

Organization

Department of the Navy

The Department of the Navy, led by the secretary of the Navy, is a military department of the cabinet-level U.S. Department of Defense that oversees the Marine Corps and the Navy. The most senior Marine Corps officer is the commandant (unless a Marine Corps officer is the chairman of the Joint Chiefs or vice chairman of the Joint Chiefs), responsible to the secretary of the Navy for organizing, recruiting, training, and equipping the Marine Corps so that its forces are ready for deployment under the operational command of the combatant commanders. The Marine Corps is organized into four principal subdivisions: Headquarters Marine Corps (HQMC), the Operating Forces, the Supporting Establishment, and the Marine Forces Reserve (MARFORRES or USMCR).

Headquarters Marine Corps

The Headquarters Marine Corps (HQMC) consists of the commandant of the Marine Corps, the assistant commandant of the Marine Corps, the director of the Marine Corps Staff, several deputy commandants, the sergeant major of the Marine Corps, and various special staff officers and Marine Corps agency heads that report directly to either the commandant or assistant commandant. HQMC is supported by the Headquarters and Service Battalion, USMC providing administrative, supply, logistics, training, and services support to the Commandant and his staff.Additionally, Marine Corps’ aircraft arm and intelligence arm are both organized under HQMC; those being the Marine Corps Aviation and Marine Corps Intelligence respectively.

Operating Forces

The Operating Forces are divided into three categories: Marine Corps Forces (MARFOR) assigned to unified combatant commands, namely, the Fleet Marine Forces (FMF); Security Forces guarding high-risk naval installations; and Security Guard detachments at American embassies. Under the “Forces for Unified Commands” memo, in accordance with the Unified Command Plan, Marine Corps Forces are assigned to each of the combatant commands at the discretion of the secretary of defense. Since 1991, the Marine Corps has maintained component headquarters at each of the regional unified combatant commands.

Marine Corps Forces are divided into Forces Command (MARFORCOM) and Pacific Command (MARFORPAC), each headed by a lieutenant general dual-posted as the commanding general of either FMF Atlantic (FMFLANT) or FMF Pacific (FMFPAC), respectively. MARFORCOM/FMFLANT has operational control of the II Marine Expeditionary Force; MARFORPAC/FMFPAC has operational control of the I Marine Expeditionary Force and III Marine Expeditionary Force.

Additional service components under the Marine Corps Forces includes: the Marine Corps Forces Europe and Africa (MARFOREUR/AF) under U.S. European Command (EURCOM) and U.S. Africa Command (AFRICOM); the Marine Corps Forces Central Command (MARFORCENT) under U.S. Central Command (CENTCOM); the Marine Corps Forces South (MARFORSOUTH) under U.S. Southern Command (SOUTHCOM); the Marine Corps Forces Cyberspace Command (MARFORCYBER) under U.S. Cyber Command (CYBERCOM); the Marine Corps Forces Space Command (MARFORSPACE) under U.S. Space Command (SPACECOM); and the Marine Corps Forces Strategic Command (MARFORSTRAT) under U.S. Strategic Command (STRATCOM).

Marine Air-Ground Task Force

The basic framework for deployable Marine units is the Marine Air-Ground Task Force (MAGTF), a flexible structure of varying size. A MAGTF integrates a ground combat element (GCE), an aviation combat element (ACE), and a logistics combat element (LCE) under a common command element (CE), capable of operating independently or as part of a larger coalition. The MAGTF structure reflects a strong preference in the Corps toward self-sufficiency and a commitment to combined arms, both essential assets to an expeditionary force.

Supporting Establishment

The Supporting Establishment includes the Combat Development Command, the Logistics Command, the Systems Command, the Training and Education Command (including Recruiting Command), the Installations Command, the Marine Band, and the Marine Drum and Bugle Corps.

Marine Corps bases and stations

The Marine Corps operates many major bases, 14 of which host operating forces, seven support and training installations, as well as satellite facilities. Marine Corps bases are concentrated around the locations of the Marine Expeditionary Forces, though reserve units are scattered throughout the U.S. The principal bases are Camp Pendleton on the West Coast, home to I Marine Expeditionary Force, Camp Lejeune on the East Coast, home to II Marine Expeditionary Force, and Camp Butler in Okinawa, Japan, home to III Marine Expeditionary Force.

Other important bases include air stations, recruit depots, logistics bases, and training commands. Marine Corps Air Ground Combat Center Twentynine Palms in California is the Marine Corps’s largest base and home to the Corps’s most complex combined-arms live-fire training.Marine Corps Base Quantico in Virginia is home to Marine Corps Combat Development Command and nicknamed the “Crossroads of the Marine Corps”.The Marine Corps maintains a significant presence in the National Capital Region, with Headquarters Marine Corps scattered among the Pentagon, Henderson Hall, Washington Navy Yard, and Marine Barracks, Washington, D.C. Additionally, Marines operate detachments at many installations owned by other branches to better share resources, such as specialty schools. Marines are also present at and operate many forward bases during expeditionary operations.

Marine Forces Reserve

The Marine Forces Reserve (MARFORRES/USMCR) consists of the Force Headquarters Group, 4th Marine Division, 4th Marine Aircraft Wing, and the 4th Marine Logistics Group. The MARFORRES/USMCR is capable of forming a 4th Marine Expeditionary Force or reinforcing/augmenting active-duty forces.

Special operations

The Marine Forces Special Operations Command (MARSOC) includes the Marine Raider Regiment, the Marine Raider Support Group, and the Marine Raider Training Center (MRTC). Both the Raider Regiment and the Raider Support Group consist of three battalions with a headquarters company. The MRTC conducts screening, assessment, selection, training and development functions for MARSOC units.

Although the notion of a Marine special operations forces contribution to the United States Special Operations Command (USSOCOM) was considered as early as the founding of USSOCOM in the 1980s, it was resisted by the Marine Corps. Commandant Paul X. Kelley expressed the belief that marines should only support marines and that the Corps should not fund a special operations capability that would not directly support Marine Corps operations. However, much of the resistance from within the Corps dissipated when Marine leaders watched the Corps’ 15th and 26th MEU(SOC)s “sit on the sidelines” during the very early stages of Operation Enduring Freedom while other conventional units and special operations units from the Army, Navy, and Air Force actively engaged in operations in Afghanistan. After a three-year development period, the Corps agreed in 2006 to supply a 2,500-strong unit, Marine Forces Special Operations Command, which would answer directly to USSOCOM.

Separate to the MARSOC, the 24th Marine Expeditionary Unit and the 26th Marine Expeditionary Unit both part of the II Marine Expeditionary Force are certified as “special operations capable” (MEU(SOC)).

Although the Marine Corps ground reconnaissance units, the Force Reconnaissance Companies and the Reconnaissance Battalions, are conventional forces and not special operations forces, they do share many of the same tactics, techniques, procedures, terms, and equipment.

Personnel

Leadership

The commandant of the Marine Corps is the highest-ranking officer of the Marine Corps, unless a Marine is either the chairman or vice chairman of the Joint Chiefs of Staff. The commandant has the U.S. Code Title 10 responsibility to staff, train, and equip the Marine Corps and has no command authority. The commandant is a member of the Joint Chiefs of Staff and reports to the secretary of the Navy.

The assistant commandant of the Marine Corps acts as the chief deputy to the commandant. The sergeant major of the Marine Corps is the senior enlisted Marine and acts as an adviser to the commandant. Headquarters Marine Corps comprises the rest of the commandant’s counsel and staff, with deputy commandants that oversee various aspects of the Corps assets and capabilities. The 39th and current commandant is Eric M. Smith, while the 20th and current sergeant major is Carlos A. Ruiz.

Women

Women have served in the United States Marine Corps since 1918. The first woman to have enlisted was Opha May Johnson (1878–1955). In January 2017, three women joined an infantry battalion at Camp Lejeune. Women had not served as infantry marines prior to this. In 2017, the Marines released a recruitment advertisement that focused on women for the first time. As of October 2019, female Marines make up 7.8% of the personnel.

In December 2020, the Marine Corps began a trial program to have females integrated into the training companies at their recruit depot in San Diego as Congress has mandated an end to the male-only program there. For the 60 female recruits, scheduled to begin training in San Diego in February 2021, the Corps will transfer female drill instructors from their recruit depot in Parris Island, which already has a coed program. Fifty-three of these recruits successfully graduated from boot camp in April 2021 and became marines.

Racial Integration

In 1776 and 1777, a dozen African American marines served in the American Revolutionary War, but from 1798 to 1942, the Marine Corps followed a racially discriminatory policy of denying African Americans the opportunity to serve. The Marine Corps was the last of the services to recruit African Americans, and its own history page acknowledges that it was a presidential order that “forced the Corps, despite objections from its leadership, to begin recruiting African American Marines in 1942. It accepted them as recruits into segregated all-black units. For the next few decades, the incorporation of black troops was not widely accepted within the Corps, nor was desegregation smoothly or quickly achieved. The integration of African American Marines proceeded in stages from segregated battalions in 1942, to unified training in 1949, and finally full integration in 1960.

The Marine Corps today is a fully integrated force, with Marines of all racial and ethnic backgrounds serving together.

Rank structure

As in the rest of the United States Armed Forces (excluding the U.S. Space Force, which does not currently appoint warrant officers), Marine Corps ranks fall into one of three categories: commissioned officer, warrant officer, and enlisted, in decreasing order of authority. To standardize compensation, each rank is assigned a pay grade.

Commissioned officers

Commissioned officers are distinguished from other officers by their commission, which is the formal written authority, issued in the name of the president of the United States, that confers the rank and authority of a Marine officer. Commissioned officers carry the “special trust and confidence” of the president of the United States. Marine Corps commissioned officers are promoted based on an “up or out” system in accordance with the Defense Officer Personnel Management Act of 1980.

Warrant officers

Warrant officers are primarily formerly enlisted experts in a specific specialized field and provide leadership generally only within that specialty.

Enlisted

Enlisted marines in the pay grades E-1 to E-3 make up the bulk of the Corps’s ranks. Although they do not technically hold leadership ranks, the Corps’s ethos stresses leadership among all marines, and junior marines are often assigned responsibilities normally reserved for superiors. Those in the pay grades of E-4 and E-5 are non-commissioned officers (NCOs). They primarily supervise junior marines and act as a vital link with the higher command structure, ensuring that orders are carried out correctly. Marines E-6 and higher are staff non-commissioned officers (SNCOs), charged with supervising NCOs and acting as enlisted advisers to the command.

The E-8 and E-9 levels have two and three ranks per pay grade, respectively, each with different responsibilities. The first sergeant and sergeant major ranks are command-oriented, serving as the senior enlisted marines in a unit, charged to assist the commanding officer in matters of discipline, administration, and the morale and welfare of the unit. Master sergeants and master gunnery sergeants provide technical leadership as occupational specialists in their specific MOS. The sergeant major of the Marine Corps is a billet conferred on the senior enlisted marine of the entire Marine Corps, personally selected by the commandant, and is given a special pay grade above E-9. It is possible for an enlisted marine to hold a position senior to Sergeant Major of the Marine Corps which was the case from 2011 to 2015 with the appointment of Sergeant Major Bryan B. Battaglia to the billet of Senior Enlisted Advisor to the chairman, who is the most senior enlisted member of the United States military, serving in the Joint Chiefs of Staff.

Military Occupational Specialty

The Military Occupational Specialty (MOS) is a system of job classification. Using a four digit code, it designates what field and specific occupation a Marine performs. Segregated between officer and enlisted, the MOS determines the staffing of a unit. Some MOSs change with rank to reflect supervisory positions; others are secondary and represent a temporary assignment outside of a Marine’s normal duties or special skill.

Initial training

Every year, over 2,000 new Marine officers are commissioned, and 38,000 recruits are accepted and trained. All new marines, enlisted or officer, are recruited by the Marine Corps Recruiting Command.

Commissioned officers are commissioned mainly through one of three sources: Naval Reserve Officer Training Corps, Officer Candidates School, or the United States Naval Academy. Following commissioning, all Marine commissioned officers, regardless of accession route or further training requirements, attend The Basic School at Marine Corps Base Quantico. At The Basic School, second lieutenants, warrant officers, and selected foreign officers learn the art of infantry and combined arms warfare.

Enlisted marines attend recruit training, known as boot camp, at either Marine Corps Recruit Depot San Diego or Marine Corps Recruit Depot Parris Island. Historically, the Mississippi River served as a dividing line that delineated who would be trained where, while more recently, a district system has ensured a more even distribution of male recruits between the two facilities. All recruits must pass a fitness test to start training; those who fail will receive individualized attention and training until the minimum standards are reached. Marine recruit training is the longest among the American military services; it is 13 weeks long including processing and out-processing.

Following recruit training, enlisted marines then attend the School of Infantry at Camp Geiger or Camp Pendleton. Infantry marines begin their combat training, which varies in length, immediately with the Infantry Training Battalion. Marines in all other MOSs train for 29 days in Marine Combat Training, learning common infantry skills, before continuing on to their MOS schools, which vary in length.

Uniforms

The Marine Corps has the most stable and most recognizable uniforms in the American military; the Dress Blues dates back to the early 19th century and the service uniform to the early 20th century. Only a handful of skills (parachutist, air crew, explosive ordnance disposal, etc.) warrant distinguishing badges, and rank insignia is not worn on uniform headgear (with the exception of an officer’s garrison service cover).

Marines have four main uniforms: dress, service, utility, and physical training. These uniforms have a few minor but very distinct variations from enlisted personnel to commissioned and non-commissioned officers. The Marine Corps dress uniform is the most elaborate, worn for formal or ceremonial occasions. There are four different forms of the dress uniform. The variations of the dress uniforms are known as “Alphas”, “Bravos”, “Charlies”, or “Deltas”. The most common being the “Blue Dress Alphas or Bravos”, called “Dress Blues” or simply “Blues”. It is most often seen in recruiting advertisements and is equivalent to black tie. There is a “Blue-White” Dress for summer, and Evening Dress for formal (white tie) occasions, which are reserved for SNCO’s and officers. Versions with a khaki shirt in lieu of the coat (Blue Dress Charlie/Delta) are worn as a daily working uniform by Marine recruiters and NROTC staff.

The service uniform was once the prescribed daily work attire in garrison; however, it has been largely superseded in this role by the utility uniform. Consisting of olive green and khaki colors. It is roughly equivalent in function and composition to a business suit.

The utility uniform, currently the Marine Corps Combat Utility Uniform, is a camouflage uniform intended for wear in the field or for dirty work in garrison, though it has been standardized for regular duty. It is rendered in MARPAT pixelated camouflage that breaks up the wearer’s shape. In garrison, the woodland and desert uniforms are worn depending on the marine’s duty station.Marines consider the utilities a working uniform and do not permit their wear off-base, except in transit to and from their place of duty and in the event of an emergency.

Culture

Official traditions and customs

As in any military organization, the official and unofficial traditions of the Marine Corps serve to reinforce camaraderie and set the service apart from others. The Corps’s embrace of its rich culture and history is cited as a reason for its high esprit de corps. An important part of the Marine Corps culture is the traditional seafaring naval terminology derived from its history with the Navy. “Marines” are not “soldiers” or “sailors”.

The Marine Corps emblem is the Eagle, Globe, and Anchor, sometimes abbreviated “EGA”, adopted in 1868. The Marine Corps seal includes the emblem, also is found on the flag of the United States Marine Corps, and establishes scarlet and gold as the official colors. The Marine motto Semper Fidelis means Always Faithful in Latin, often appearing as Semper Fi. The Marines’ Hymn dates back to the 19th century and is the oldest official song in the United States armed forces. Semper Fi is also the name of the official march of the Corps, composed by John Philip Sousa. The mottos “Fortitudine” (With Fortitude); By Sea and by Land, a translation of the Royal Marines’ Per Mare, Per Terram; and To the Shores of Tripoli were used until 1868.

Two styles of swords are worn by marines: the officers’ Mameluke Sword, similar to the Persian shamshir presented to Lt. Presley O’Bannon after the Battle of Derna, and the Marine NCO sword. The Marine Corps Birthday is celebrated every year on 10 November in a cake-cutting ceremony where the first slice of cake is given to the oldest marine present, who in turn hands it off to the youngest marine present. The celebration includes a reading of Commandant Lejeune’s Birthday Message. Close Order Drill is heavily emphasized early on in a marine’s initial training, incorporated into most formal events, and is used to teach discipline by instilling habits of precision and automatic response to orders, increase the confidence of junior officers and noncommissioned officers through the exercise of command and give marines an opportunity to handle individual weapons.

Unofficial traditions and customs

Marines have several generic nicknames:

Devil Dog: German soldiers during the First World War reportedly said at Belleau Wood that the marines were so vicious that the German infantrymen called them Teufelshunde – ‘devil dogs’.

Gyrene: commonly used between fellow marines.

Leatherneck: refers to a leather collar formerly part of the Marine uniform during the Revolutionary War period.

Jarhead has several oft-disputed explanations.

Crayon-eater: A self-deprecating term originating in the 2010s, playing off of a stereotype of Marines as unintelligent.

Some other unofficial traditions include mottos and exclamations:

Oorah is common among marines, being similar in function and purpose to the Army, Air Force, and Space Force’s hooah and the Navy’s hooyah cries. Many possible etymologies have been offered for the term.

Semper Fi is a common greeting among serving and veteran marines.

Improvise, Adapt and Overcome has become an adopted mantra in many units.

Negative associations

In 1976 the Camp Pendleton Chapter of the Ku Klux Klan, which had over 100 members, was headed by an active duty marine. In 1986, a number of Marines were implicated in the theft of weapons for the White Patriot Party. While the sale of the weapons was to a supremacist organization it was never verified that the Marines were actual members of the organization. The USMC, along with the rest of the military, has since made an effort to address extremism in the ranks.

Veteran marines

The Corps encourages the idea that “Marine” is an earned title, and most Marine Corps personnel take to heart the phrase “Once a Marine, always a Marine”. They reject the term “ex-Marine” in most circumstances. There are no regulations concerning the address of persons who have left active service, so a number of customary terms have come into common use.

Martial arts program

In 2001, the Marine Corps initiated an internally designed martial arts program, called Marine Corps Martial Arts Program (MCMAP). Because of an expectation that urban and police-type peacekeeping missions would become more common in the 21st century, placing marines in even closer contact with unarmed civilians, MCMAP was implemented to provide marines with a larger and more versatile set of less-than-lethal options for controlling hostile, unarmed individuals. It is a stated aim of the program to instill and maintain the “Warrior Ethos” within marines.

The MCMAP is an eclectic mix of different styles of martial arts melded together. MCMAP consists of punches and kicks from Taekwondo and Karate, opponent weight transfer from Jujitsu, ground grappling involving joint locking techniques and chokes from Brazilian jiu-jitsu, and a mix of knife and baton/stick fighting derived from Eskrima, and elbow strikes and kick boxing from Muay Thai. Marines begin MCMAP training in boot camp, where they will earn the first of five available belts. The belts begin at tan and progress to black and are worn with standard utility uniforms.

Equipment

As of 2013, the typical infantry rifleman carries $14,000 worth of gear (excluding night-vision goggles), compared to $2,500 a decade earlier. The number of pieces of equipment (everything from radios to trucks) in a typical infantry battalion has also increased, from 3,400 pieces of gear in 2001 to 8,500 in 2013.

Infantry weapons

The infantry weapon of the Marine Corps is the M27 IAR service rifle. Most non-infantry marines have been equipped with the M4 carbine or Colt 9mm SMG.The standard side arm is the SIG Sauer M17/M18 The M18 will replace all other pistols in the Marine Corps inventory, including the M9, M9A1, M45A1 and M007, as the M45A1 Close Quarter Battle Pistol (CQBP) in small numbers. Suppressive fire is provided by the, M249 SAW, and M240 machine guns, at the squad and company levels respectively. In 2018, the M27 IAR was selected to be the standard-issue rifle for all infantry squads. In 2021, the Marine Corps committed to fielding suppressors to all its infantry units, making it the first branch of the U.S. military to adopt them for widespread use.

The USMC infantry issued grenade launcher is the M320, which shoots a 40 mm grenade, such as the M67 fragmentation grenade.[180] Indirect fire is also provided by the M203 grenade launcher and the M32 grenade launcher in fireteams, M224 60 mm mortar in companies, and M252 81 mm mortar in battalions. The M2 .50 caliber heavy machine gun and MK19 automatic grenade launcher (40 mm) are available for use by dismounted infantry, though they are more commonly vehicle-mounted. Precision firepower is provided by the M40 series and the Barrett M107, while designated marksmen use the DMR variant of the M27, known as the M38, and the SAM-R.

The Marine Corps uses a variety of direct-fire rockets and missiles to provide infantry with an offensive and defensive anti-armor capability. The Mk 153 SMAW and AT4 are unguided rockets that can destroy armor and fixed defenses (e.g., bunkers) at ranges up to 500 meters. The smaller and lighter M72 LAW can destroy targets at ranges up to 200 meters. The FGM-172 SRAW, FGM-148 Javelin and BGM-71 TOW are anti-tank guided missiles. The Javelin can use top-attack profiles to avoid heavy frontal armor. The SRAW is a close range missile system that uses a Predicted Line of Sight (PLOS) guidance system. The Javelin and TOW are heavier missiles effective past 2,000 meters that give infantry an offensive capability against armor.

Ground vehicles

The Corps operates the same HMMWV as does the Army, which is in the process of being replaced by the Joint Light Tactical Vehicle (JLTV). However, for its specific needs, the Corps uses a number of unique vehicles. The LAV-25 is a dedicated wheeled armored personnel carrier, similar to the Army’s Stryker vehicle, used to provide strategic mobility.Amphibious capability is provided by the AAV-7A1 Assault Amphibious Vehicle, an armored tracked vehicle that doubles as an armored personnel carrier, due to be replaced by the Amphibious Combat Vehicle, a faster vehicle with superior armor and weaponry. The threat of land mines and improvised explosive devices in Iraq and Afghanistan has seen the Corps begin purchasing heavily armored vehicles that can better withstand the effects of these weapons as part of the Mine Resistant Ambush Protected vehicle program.

The Marines also operate the M777 155 mm howitzer and the High Mobility Artillery Rocket System (HIMARS), a truck-mounted rocket artillery system. Both are capable of firing guided munitions. In 2020, the Marine Corps retired its M1A1 Abrams tanks and eliminated all of its tank units. General David Berger explained the decision describing the long-serving Marine weapons system as “operationally unsuitable for our highest-priority challenges.” The move leaves the Army as the sole American operator of tanks.

Aircraft

The organic aviation capability of the Marine Corps is essential to its amphibious mission. Marine Corps Aviation operates both rotary-wing and fixed-wing aircraft mainly to provide Assault Support and close air support to its ground forces. Other aircraft types are used in a variety of support and special-purpose roles. The light transport and attack capabilities are provided by the Bell UH-1Y Venom and Bell AH-1Z Viper. Medium-lift squadrons use the MV-22 Osprey tiltrotor. Heavy-lift squadrons are equipped with the CH-53E Super Stallion helicopter, which are being replaced with the upgraded CH-53K.

Marine attack squadrons fly the AV-8B Harrier II; while the fighter/attack mission is handled by the single-seat and dual-seat versions of the F/A-18 Hornet strike-fighter aircraft. The AV-8B is a V/STOL aircraft that can operate from amphibious assault ships, land air bases and short, expeditionary airfields, while the F/A-18 can only be flown from land or aircraft carriers. Both are slated to be replaced by 340 of the STOVL B version of the F-35 Lightning IIand 80 of the carrier F-35C versions for deployment with Navy carrier air wings.

The Corps operates its own organic aerial refueling assets in the form of the KC-130 Hercules; however, it also receives a large amount of support from the U.S. Air Force. The Hercules doubles as a ground refueler and tactical-airlift transport aircraft. The USMC electronic warfare plane, the EA-6B, was retired in 2019. The Marines operate unmanned aerial vehicles: the RQ-7 Shadow and Scan Eagle for tactical reconnaissance.

Marine Fighter Training Squadron 401 (VMFT-401), operates F-5E, F-5F and F-5N Tiger II aircraft in support of air combat adversary (aggressor) training. Marine Helicopter Squadron One (HMX-1) operates the VH-3D Sea King and VH-60N Whitehawk helicopters in the VIP transport role, most notably Marine One, but are due to be replaced with the VH-92 Patriot. A single Marine Corps C-130 Hercules aircraft, “Fat Albert”, is used to support the U.S. Navy’s flight demonstration team, the “Blue Angels”.

Relationship with other services

In general, the Marine Corps shares many resources with the other branches of the United States Armed Forces. However, the Corps has consistently sought to maintain its own identity with regard to mission, funding, and assets, while using support available from the larger branches. While the Marine Corps has far fewer installations both in the U.S. and worldwide than the other branches, many Army posts, Naval stations, and Air Force bases have a Marine presence. They also cross-train with other countries.

United States Navy

The Marine Corps’s counterpart under the Department of the Navy is the United States Navy. As a result, the Navy and Marine Corps have a close relationship, more so than with other branches of the military. White papers and promotional literature have commonly used the phrase “Navy-Marine Corps Team”,or refer to “the Naval Service”. Both the chief of naval operations (CNO) and commandant of the Marine Corps report directly to the secretary of the Navy.

Operationally, the Marine Corps provides the Fleet Marine Forces for service with the Navy’s fleets, including the forward-deployed Marine Expeditionary Units embarked aboard Navy amphibious warships. The Corps also contributes some Marine Aviation fixed-wing fighter/attack assets (aircraft squadrons and related aircraft maintenance augmentation units) as part of the Carrier Air Wings deployed aboard aircraft carriers. The Marine Corps Security Force Regiment provides infantry-based security battalions and Fleet Anti-terrorism Security Team companies to guard and defend high-priority and overseas Navy bases. Security for the Presidential Retreat located aboard the Naval Support Activity Thurmont, aka Camp David is provided by the Marine infantry battalion stationed as part of the garrison aboard Marine Barracks Washington.

Cooperation between the two services includes the training and instruction of some future Marine Corps officers (most are trained and commissioned through Marine Corps OCS), all Marine Corps Naval Aviators (aircraft pilots) and Naval Flight Officers (airborne weapons and sensor system officers), and some Navy and Marine Corps enlisted personnel. The Corps receives a significant portion of its officers from the United States Naval Academy (USNA) and Naval Reserve Officers Training Corps (NROTC). USNA and NROTC staff and faculty includes Marine Corps instructors. Marine Corps aviators and flight officers are trained in the Naval Air Training Command (NATRACOM) and are designated, or winged as Naval Aviators or Naval Flight Officers. The Marine Corps provides flight instructors to the Naval Air Training Command as well as drill instructors to the Navy’s Officer Candidate School. Many enlisted marines, particularly those in the aviation maintenance specialties, are trained at Navy technical training centers. The Marine Corps also provides ground combat training support to various Navy field medical (Hospital Corpsmen), Naval Construction Force (Seabee), and Navy Expeditionary Warfare personnel, units, and commands.

Training alongside each other is viewed as critical, as the Navy provides transport, logistical, and combat support to put Marine units into the fight, such as maritime prepositioning ships and naval gunfire support. Most Marine aviation assets ultimately derive from the Navy, with regard to acquisition, funding, and testing, and Navy aircraft carriers typically deploy with a Marine squadron alongside Navy squadrons. Marines do not recruit or train noncombatants such as chaplains or medical/dental personnel; naval personnel fill these roles. Some of these sailors, particularly Hospital corpsmen and Religious program specialists, generally wear Marine uniforms emblazoned with Navy insignia. Conversely, the Marine Corps is responsible for conducting land operations to support naval campaigns, including the seizure of naval bases. Both services operate a network security team in conjunction.

Marines and sailors share many naval traditions, especially terminology and customs. Marine Corps Medal of Honor recipients wear the Navy variant of this and other awards; and with few exceptions, the awards and badges of the Navy and Marine Corps are identical. Much of testing for new Marine Corps aircraft is done at Naval Air Station Patuxent River. The Navy’s Blue Angels flight demonstration team is staffed by both Navy and Marine officers and enlisted personnel.

In 2007, the Marine Corps joined with the Navy and Coast Guard to adopt a new maritime strategy called A Cooperative Strategy for 21st Century Seapower that raises the notion of prevention of war to the same philosophical level as the conduct of war. This new strategy charts a course for the Navy, Coast Guard and Marine Corps to work collectively with each other and international partners to prevent regional crises, human-made or natural, from occurring or reacting quickly should one occur to avoid negative impacts to the United States.

United States Army

The Marine Corps capabilities overlap with those of the United States Army, historically creating competition for funding and missions. The competition dates back to the founding of the Continental Marines, when General George Washington refused to allow the initial Marine battalions to be drawn from among his Continental Army. In the aftermath of World War II, Army leadership made efforts to restructure the American defense establishment including the dissolution of the Marine Corps and the folding of its capabilities into the other services. Leading this movement were such prominent Army officers as General Dwight D. Eisenhower and Army chief of staff George C. Marshall.

The Goldwater-Nichols Act significantly reshaped the services roles and relationships with each other, enforcing more joint decision making. Department of Defense Directive 5100.01 tasks both the Army and Marine Corps with expeditionary and amphibious operations. With most of the 2000s spent in operations in Afghanistan and Iraq, Secretary of Defense Robert Gates voiced concerns that the Marine Corps are becoming a “second Army”. Since these comments, the Marine Corps has shed its main battle tanks, reduced its size, and focused more on operations in littoral areas where the Army is not explicitly tasked to operate.

The Army maintains much larger and diverse combat arms, special operations, and logistics forces. The Army has much lighter and expeditionary forces in its infantry and airborne infantry brigade combat teams. The Army also maintains heavier and more logistically taxing armored brigade combat teams. The Marine Corps, in comparison, maintains forces between these two extremes of mobility and protection. The Marine Corps organizes much smaller deployable units with integrated aviation support. The Marine Corps was historically hesitant to provide forces to U.S. Special Operations Command, instead making specialty units available to its division commanders. The Army has maintained Special Forces, Rangers, civil affairs, psychological operations, special operations aviation, and special missions units for decades. In 2003, the Marine Corps created the present-day successors to the Marine Raiders and provided them to Special Operations Command starting with the establishment of MCSOCOM Detachment One. The modern Marine Raider training pipeline was based on input from U.S. Army Ranger and Special Forces units.

Culturally, marines and soldiers share most of the common U.S. military slang and terminology, but the Corps uses a large number of naval terms and traditions incompatible with Army lifestyle, as well as its own unique vernacular. As the Army Reserve and Army National Guard is much larger than the Marine Corps’s Reserve, many more former active duty marines continue their service in the Army’s reserve components. The Army does not require transfers from the Marines, Air Force Security Forces, or special operations of any branch to attend Army Basic Combat Training. Due to the requirement that all inter-service transfers attend Marine Corps Recruit Training, very few former soldiers serve in the Marine Corps.

United States Air Force

While some of Marine Corps Aviation assets ultimately derive from the Navy, a large amount of support is drawn from the United States Air Force. The Marine Corps makes extensive use of the USAF Air Mobility Command to airlift marines and equipment, along with using close air support from the Air Force. The Air Force may also attach Tactical Air Control Party units to conventional Marine ground forces to provide coordination for close air support.

The Air Force traditionally provides the Joint Force Air Component Commander (JFACC) who controls “sorties for air defense, and long range interdiction and reconnaissance” while the MAGTF commander retains control of the Marines’ organic aviation assets, however Marine Aviation missions not directly in the support of the MAGTF will be typically controlled by the JFACC.

United States Coast Guard

The Marine Corps shares a sphere of operation with units of the United States Coast Guard, including operation of the Joint Maritime Training Center (JMTC) (previously known as the Special Missions Training Center (SMTC)), a joint Coast Guard, Navy, and Marine Corps training facility located on the Marine Corps Base Camp Lejeune in Camp Lejeune, North Carolina.

Budget

Military Personnel	13,197	13,888
Reserve Personnel	763	785
Medicare-Eligible Retiree Health Fund Contribution	903	831
Medicare-Eligible Retiree Health Fund Contribution, Reserves	81	74
Operation and Maintenance	8,118	7,843
Operation and Maintenance, Reserve	287	275
Procurement	2,019	2,858
Procurement of Ammunition, Navy/Marine Corps	1,038*	1,182*
Military Construction, Navy and Marine Corps	1,993*	2,593*
Total Appropriated	28,399	30,329

For more https://www.marines.com/

March 24, 2025

CorelDRAW Graphics Suite 2025 License Key Activation Key

CorelDRAW Graphics Suite 2024 License Key

SDFGHJHGF-DFGH-FDS-DFGH-DFGHJ-HGFDS-DFGTE5
SDFGHG-FDSD-FGHJ-GFDS-DFCGHNBVGFXDZ-RTE54E
SDFG-FDSZFD-GHDGFZSX-BFHGSER-SDXHGF-EWRT4R
SZFDGDSEAE-SRFCV-XDFG-RTEAW-SZDB-CVCHGFDSS
XCGFDSA-XCFGEWERTGF-HGFD-RESXC-VCFSSHGFDSZ
XCVGF-DFGHB-VCXDFG-HYT-RERTY-HGFDCVBHGFDSC
VBHGFDE-RTGHBV-BN-HGRE-RTGFCV-BGFD-EHGFDSV
XCVBG-FDRFTG-YTRE-DFV-CDCFG-HGTR-TGFDHGFDSB
CVBGF-DSWERTGY-TREW-SDFVH-GTRE-RTRDCHGFDSN
JFRBL-PIOT9-TU430-B90NH-VC9KK
ZV0UR-GGG17-NAFCK-MHHWH-89M32
8FMUK-0J72C-0NEX7-JUELG-7PCX3
35IZ7-SDY0I-AOJNX-4Q5SC-SZPKM

CorelDRAW Graphics Suite 2023 Activation Key

FDGHGTYR5-WEASDG-DFMHYRJEY5T4W-RQAFDSGHJHG
DSGFTRWT-EFSDGFDHTQR-ASFDGFDH-THERGE-ASDGFS
ADSFRWQR-AFSGHRETQRE-SDFTRY-TWERAFDSGDHG-TR
DFDRTRQ-WaDSFDGTHER-SFDGGF-HGTGDERWD-FGTRED
NCHJR-ZGMWG-TCAOT-OFWGH-GM81J
PQ3CD-ADPA1-DP1E9-N5IQG-NAT64
C05XO-O66IF-415ZA-3S9CI-A1VT6
OQ9O3-KEL0V-TYHKW-1CEQA-PIWOO

License Key

SAGHGH-HSXDFYHSJH-SDGHED-DHDFGH-DFG
SGHEDH-DHRY-DTHMNB-DRYDEN-YRNDB-BGFC
RNYHR-5RUM-YNFHT-YNHGSE-DRUYD-DTYGHJ
TFHTU-DTHG-CGFJDT-DHT-FGHG-EYTR-RHNTSE

CorelDRAW Graphics Suite Activation Key

ASDREYTRWAS-FZDGHRYET4WRWASF-DGHRYTWE
DSGRYWT4ESDGFHD-TJUEY4WTRWASFG-DSRETSS
DFGTEUY5TERSFGFH-GJTEYRT4WRSDF-FHGTREDFC
GRESDFGHYTRED-FGHYTRESDCV-BHTREWERTGYH

CorelDRAW Graphics Suite X7Purchase serial number:

DR17R16-LVYRU7E-M3PZDRD-6968GV4
Activation Code:
E67F-80D7-0B74-CE4C-EBC3

CorelDRAW Graphics Suite X7Purchase serial number:

DR17R28-2L5DZHC-WTQNJQX-2GSX5PS
Activation Code:
DD9F-5D29-E6BA-6730-027B

March 15, 2025
Aga Khan

February 5, 2025
Lisa Su

February 5, 2025

First law:	In an inertial reference frame, an object either remains at rest or continues to move in a straight line at a constant velocity, unless acted upon by a net force.
Second law:	In an inertial reference frame, the vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration a of the object: F→=ma→ ${\vec {F}}=m{\vec {a}}$ .If the resultant force F→ ${\vec {F}}$ acting on a body or an object is not equal to zero, the body will have an acceleration a $a$ that is in the same direction as the resultant force.
Third law:	When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction onto the first body.