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Selection of weapons collected by security officers at an airport Dangerous weapons seized from holiday flights at Manchester Airport.jpg
Selection of weapons collected by security officers at an airport

A weapon, arm or armament is any implement or device that can be used with intent to inflict damage or harm. Weapons are used to increase the efficacy and efficiency of activities such as hunting, crime, law enforcement, self-defense, and warfare. In broader context, weapons may be construed to include anything used to gain a tactical, strategic, material or mental advantage over an adversary or enemy target.


While ordinary objects – sticks, rocks, bottles, chairs, vehicles – can be used as weapons, many are expressly designed for the purpose; these range from simple implements such as clubs, axes and swords, to complicated modern firearms, tanks, intercontinental ballistic missiles, biological weapons, and cyberweapons. Something that has been re-purposed, converted, or enhanced to become a weapon of war is termed weaponized, such as a weaponized virus or weaponized laser.



An array of Neolithic artifacts, including bracelets, axe heads, chisels, and polishing tools. Neolithique 0001.jpg
An array of Neolithic artifacts, including bracelets, axe heads, chisels, and polishing tools.

The use of objects as weapons has been observed among chimpanzees, [1] leading to speculation that early hominids used weapons as early as five million years ago. [2] However, this can not be confirmed using physical evidence because wooden clubs, spears, and unshaped stones would have left an ambiguous record. The earliest unambiguous weapons to be found are the Schöningen spears, eight wooden throwing spears dating back more than 300,000 years. [3] [4] [5] [6] [7] At the site of Nataruk in Turkana, Kenya, numerous human skeletons dating to 10,000 years ago may present evidence of traumatic injuries to the head, neck, ribs, knees and hands, including obsidian projectiles embedded in the bones that might have been caused from arrows and clubs during conflict between two hunter-gatherer groups. [8] But the evidence interpretation of warfare at Nataruk has been challenged. [9]

Ancient history

A four-wheeled ballista drawn by armored cataphract horses, c. 400. Ballista-quadrirotis.jpeg
A four-wheeled ballista drawn by armored cataphract horses, c.400.

The earliest ancient weapons were evolutionary improvements of late neolithic implements, but significant improvements in materials and crafting techniques led to a series of revolutions in military technology.

The development of metal tools began with copper during the Copper Age (about 3,300 BC) and was followed by the Bronze Age, leading to the creation of the Bronze Age sword and similar weapons.

During the Bronze Age, the first defensive structures and fortifications appeared as well, [10] indicating an increased need for security. Weapons designed to breach fortifications followed soon after, such as the battering ram, which was in use by 2500 BC. [10]

The development of iron-working around 1300 BC in Greece had an important impact on the development of ancient weapons. It was not the introduction of early Iron Age swords, however, as they were not superior to their bronze predecessors, but rather the domestication of the horse and widespread use of spoked wheels by c. 2000 BC. [11] This led to the creation of the light, horse-drawn chariot, whose improved mobility proved important during this era. [12] Spoke-wheeled chariot usage peaked around 1300 BC and then declined, ceasing to be militarily relevant by the 4th century BC. [13]

Cavalry developed once horses were bred to support the weight of a human. [14] The horse extended the range and increased the speed of attacks.

In addition to land based weaponry, warships, such as the trireme, were in use by the 7th century BC. [15]

Post-classical history

Medieval Indian weapons Racinet1.jpg
Medieval Indian weapons
Ancient Chinese cannon displayed in the Tower of London. Tower of London interior.jpg
Ancient Chinese cannon displayed in the Tower of London.

European warfare during the Post-classical history was dominated by elite groups of knights supported by massed infantry (both in combat and ranged roles). They were involved in mobile combat and sieges which involved various siege weapons and tactics. Knights on horseback developed tactics for charging with lances providing an impact on the enemy formations and then drawing more practical weapons (such as swords) once they entered into the melee. By contrast, infantry, in the age before structured formations, relied on cheap, sturdy weapons such as spears and billhooks in close combat and bows from a distance. As armies became more professional, their equipment was standardized and infantry transitioned to pikes. Pikes are normally seven to eight feet in length, and used in conjunction with smaller side-arms (short sword).

In Eastern and Middle Eastern warfare, similar tactics were developed independent of European influences.

The introduction of gunpowder from the Asia at the end of this period revolutionized warfare. Formations of musketeers, protected by pikemen came to dominate open battles, and the cannon replaced the trebuchet as the dominant siege weapon.

Modern history

Early modern

The European Renaissance marked the beginning of the implementation of firearms in western warfare. Guns and rockets were introduced to the battlefield.

Firearms are qualitatively different from earlier weapons because they release energy from combustible propellants such as gunpowder, rather than from a counter-weight or spring. This energy is released very rapidly and can be replicated without much effort by the user. Therefore even early firearms such as the arquebus were much more powerful than human-powered weapons. Firearms became increasingly important and effective during the 16th century to 19th century, with progressive improvements in ignition mechanisms followed by revolutionary changes in ammunition handling and propellant. During the U.S. Civil War new applications of firearms including the machine gun and ironclad warship emerged that would still be recognizable and useful military weapons today, particularly in limited conflicts. In the 19th century warship propulsion changed from sail power to fossil fuel-powered steam engines.

The bayonet is used as both knife and, when attached to a rifle, a polearm. Prussian bayonet clean.jpg
The bayonet is used as both knife and, when attached to a rifle, a polearm.

Since the mid-18th century North American French-Indian war through the beginning of the 20th century, human-powered weapons were reduced from the primary weaponry of the battlefield yielding to gunpowder-based weaponry. Sometimes referred to as the "Age of Rifles", [16] this period was characterized by the development of firearms for infantry and cannons for support, as well as the beginnings of mechanized weapons such as the machine gun. Of particular note, Howitzers were able to destroy masonry fortresses and other fortifications, and this single invention caused a Revolution in Military Affairs (RMA), establishing tactics and doctrine that are still in use today. See Technology during World War I for a detailed discussion.

Industrial age

The Vickers was the successor to the Maxim gun and remained in British military service for 79 consecutive years. Vickers machine gun in the Battle of Passchendaele - September 1917.jpg
The Vickers was the successor to the Maxim gun and remained in British military service for 79 consecutive years.
Assault rifle CZ-805 BREN (produced in Czech Republic). Cz805.png
Assault rifle CZ-805 BREN (produced in Czech Republic).

An important feature of industrial age warfare was technological escalation – innovations were rapidly matched through replication or countered by another innovation. The technological escalation during World War I (WW I) was profound, including the wide introduction of aircraft into warfare, and naval warfare with the introduction of aircraft carriers.

World War I

World War I marked the entry of fully industrialized warfare as well as weapons of mass destruction (e.g., chemical and biological weapons), and new weapons were developed quickly to meet wartime needs. Above all, it promised to the military commanders the independence from the horse and the resurgence in maneuver warfare through extensive use of motor vehicles. The changes that these military technologies underwent before and during the Second World War were evolutionary, but defined the development for the rest of the century.


This period of innovation in weapon design continued in the inter-war period (between WW I and WW II) with continuous evolution of weapon systems by all major industrial powers. The major armament firms were the Schneider-Creusot (based in France), the Škoda Works (Czechoslovakia), and Vickers (Great Britain). The 1920s were committed to disarmament and outlawing of war and poison gas, but rearmament picked up rapidly in the 1930s. The munitions makers responded nimbly to the rapidly shifting strategic and economic landscape. The main purchasers of munitions from the big three companies were Romania, Yugoslavia, Greece, and Turkey-- and, to a lesser extent, in Poland, Finland, the Baltic States, and the Soviet Union, [17]

Criminalizing poison gas

Realistic critics understood that war could not really be outlawed, but its worst excesses might be banned. Poison gas became the focus of a worldwide crusade in the 1920s. Poison gas did not win battles, and the generals did not want it. The soldiers hated it far more intensely than bullets or explosive shells. By 1918, chemical shells made up 35 per cent of French ammunition supplies, 25 per cent of British, and 20 per cent of the American stock. The “Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous, or Other Gases and of Bacteriological Methods of Warfare” ["Geneva Protocol"] was issued in 1925, and was accepted as policy by all major countries. In 1937 poison gas was manufactured in large quantities, but not used except against nations that lacked modern weapons or gas masks. [18] [19]

World War II

Many modern military weapons, particularly ground-based ones, are relatively minor improvements of weapon systems developed during World War II. See military technology during World War II for a detailed discussion. World War II however, perhaps marked the most frantic period of weapons development in the history of humanity. Massive numbers of new designs and concepts were fielded, and all existing technologies were improved between 1939 and 1945. The most powerful weapon invented during this period was the atomic bomb, however many other weapons influenced the world, such as jet planes and radar, but were overshadowed by the visibility of nuclear weapons And long-range rockets.

Nuclear weapons

Since the realization of mutually assured destruction (MAD), the nuclear option of all-out war is no longer considered a survivable scenario. During the Cold War in the years following World War II, both the United States and the Soviet Union engaged in a nuclear arms race. Each country and their allies continually attempted to out-develop each other in the field of nuclear armaments. Once the joint technological capabilities reached the point of being able to ensure the destruction of the Earth x100 fold, then a new tactic had to be developed. With this realization, armaments development funding shifted back to primarily sponsoring the development of conventional arms technologies for support of limited wars rather than total war. [20]


By user

– what person or unit uses the weapon

By function

– the construction of the weapon and principle of operation

By target

– the type of target the weapon is designed to attack

Manufacture of weapons

The arms industry is a global industry that involves the sales and manufacture of weaponry. It consists of a commercial industry involved in the research and development, engineering, production, and servicing of military material, equipment, and facilities. Many industrialized countries have a domestic arms-industry to supply their own military forces - and some also have a substantial trade in weapons for use by its citizens, for self-defence, hunting or sporting purposes.

Contracts to supply a given country's military are awarded by governments, making arms contracts of substantial political importance. The link between politics and the arms trade can result in the development a "military-industrial complex", where the armed forces, commerce, and politics become closely linked.

According to research institute SIPRI, the volume of international transfers of major weapons in 2010–14 was 16 percent higher than in 2005–2009 [22] , and the arms sales of the world’s 100 largest private arms-producing and military services companies totalled $420 billion in 2018. [23]


The production, possession, trade and use of many weapons are controlled. This may be at a local or central government level, or international treaty. Examples of such controls include:

Gun laws

All countries have laws and policies regulating aspects such as the manufacture, sale, transfer, possession, modification and use of small arms by civilians.

Countries which regulate access to firearms will typically restrict access to certain categories of firearms and then restrict the categories of persons who may be granted a license for access to such firearms. There may be separate licenses for hunting, sport shooting (a.k.a. target shooting), self-defense, collecting, and concealed carry, with different sets of requirements, permissions, and responsibilities.

Arms control laws

International treaties and agreements place restrictions upon the development, production, stockpiling, proliferation and usage of weapons from small arms and heavy weapons to weapons of mass destruction. Arms control is typically exercised through the use of diplomacy which seeks to impose such limitations upon consenting participants, although it may also comprise efforts by a nation or group of nations to enforce limitations upon a non-consenting country.

Arms trafficking laws

Arms trafficking is the trafficking of contraband weapons and ammunition. What constitutes legal trade in firearms varies widely, depending on local and national laws.

Lifecycle problems

There are a number of issue around the potential ongoing risks from deployed weapons, the safe storage of weapons, and their eventual disposal when no longer effective or safe.

In science fiction

Strange and exotic weapons are a recurring feature or theme in science fiction. In some cases, weapons first introduced in science fiction have now been made a reality. Other science fiction weapons remain purely fictional, and are often beyond the realms of known physical possibility.

At its most prosaic, science fiction features an endless variety of sidearms, mostly variations on real weapons such as guns and swords. Among the best-known of these are the phaser used in the Star Trek television series, films and novels and the lightsaber and blaster featured in the Star Wars movies, comics, novels and TV series.

In addition to adding action and entertainment value, weaponry in science fiction sometimes become themes when they touch on deeper concerns, often motivated by contemporary issues. One example is science fiction that deals with weapons of mass destruction.

See also

Related Research Articles

Artillery Long-ranged guns for land warfare

Artillery is a class of heavy military ranged weapons built to launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and led to heavy, fairly immobile siege engines. As technology improved, lighter, more mobile field artillery cannons developed for battlefield use. This development continues today; modern self-propelled artillery vehicles are highly mobile weapons of great versatility generally providing the largest share of an army's total firepower.

Crossbow Type of pre-gunpowder ranged weapon

A crossbow is a ranged weapon using an elastic launching device similar to a bow; it consists of a bow-like assembly called a prod, mounted horizontally on a main frame called a tiller, which is hand-held in a similar fashion to the stock of a long gun. Crossbows shoot arrow-like projectiles called bolts or quarrels. A person who shoots crossbow is called a crossbowman or an arbalist.

Firearm Gun for an individual

A firearm is any type of gun designed to be readily carried and used by an individual. The term is legally defined further in different countries.

Arms control is a term for international restrictions upon the development, production, stockpiling, proliferation and usage of small arms, conventional weapons, and weapons of mass destruction. Arms control is typically exercised through the use of diplomacy which seeks to impose such limitations upon consenting participants through international treaties and agreements, although it may also comprise efforts by a nation or group of nations to enforce limitations upon a non-consenting country.

Chemical warfare Using poison gas or other toxins in war

Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from nuclear warfare, biological warfare and radiological warfare, which together make up CBRN, the military acronym for nuclear, biological, and chemical, all of which are considered "weapons of mass destruction" (WMDs). None of these fall under the term conventional weapons which are primarily effective due to their destructive potential. In theory, with proper protective equipment, training, and decontamination measures, the primary effects of chemical weapons can be overcome. In practice, they continue to cause much suffering, as most victims are defenseless. Many nations possess vast stockpiles of weaponized agents in preparation for wartime use. The threat and the perceived threat have become strategic tools in planning both measures and counter-measures.

Military technology application of technology for use in warfare

Military technology is the application of technology for use in warfare. It comprises the kinds of technology that are distinctly military in nature and not civilian in application, usually because they lack useful or legal civilian applications, or are dangerous to use without appropriate military training.

Non-lethal weapon weapon intended to be less likely to kill a living target than conventional weapons. In Titanfall 3, using non-lethal weapons and ammunitions are pacifist way to complete the length non-linear single-player campaign

Non-lethal weapons, also called less-lethal weapons, less-than-lethal weapons, non-deadly weapons, compliance weapons, or pain-inducing weapons are weapons intended to be less likely to kill a living target than conventional weapons such as knives and firearms. It is often understood that unintended or incidental casualties are risked wherever force is applied, but non-lethal weapons try to minimise the risk of casualties as much as possible. Non-lethal weapons are used in policing and combat situations to limit the escalation of conflict where employment of lethal force is prohibited or undesirable, where rules of engagement require minimum casualties, or where policy restricts the use of conventional force. These weapons occasionally cause serious injuries or death; the term "less-lethal" has been preferred by some organizations as it describes the risks of death more accurately than the term "non-lethal", which some have argued is a misnomer.

Siege engine Pre-gunpowder fortress-warfare machines

A siege engine is a device that is designed to break or circumvent heavy castle doors, thick city walls and other fortifications in siege warfare. Some are immobile, constructed in place to attack enemy fortifications from a distance, while others have wheels to enable advancing up to the enemy fortification. There are many distinct types, such as siege towers that allow foot soldiers to scale walls and attack the defenders, battering rams that damage walls or gates, and large ranged weapons that attack from a distance by launching projectiles. Some complex siege engines were combinations of these types.

United Kingdom and weapons of mass destruction nuclear power of United Kingdom

The United Kingdom possesses, or has possessed, a variety of weapons of mass destruction, including nuclear, biological, and chemical weapons. The United Kingdom is one of the five official nuclear weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons and has an independent nuclear deterrent. The UK has been estimated to have a stockpile of 120 active nuclear warheads and 215 nuclear warheads in total. It had renounced the use of chemical and biological weapons in 1956 and subsequently destroyed its general stocks.

Arms industry industrial sector which manufactures weapons and military technology and equipment

The arms industry, also known as the arms trade, is a global industry which manufactures and sells weapons and military technology, and is a major component of the military–industrial complex. It consists of a commercial industry involved in the research and development, engineering, production, and servicing of military material, equipment, and facilities. Arms-producing companies, also referred to as arms dealers, or as the military industry, produce arms for the armed forces of states and for civilians. Departments of government also operate in the arms industry, buying and selling weapons, munitions and other military items. An arsenal is a place where arms and ammunition - whether privately or publicly owned - are made, maintained and repaired, stored, or issued, in any combination. Products of the arms industry include guns, artillery, ammunition, missiles, military aircraft, military vehicles, ships, electronic systems, night-vision devices, holographic weapon sights, laser rangefinders, laser sights, hand grenades, landmines and more. The arms industry also provides other logistical and operational support.

Space warfare is combat that takes place in outer space. The scope of space warfare therefore includes ground-to-space warfare, such as attacking satellites from the Earth; space-to-space warfare, such as satellites attacking satellites; and space-to-ground warfare, such as satellites attacking Earth-based targets.

Early thermal weapons category of historical weapons

Early thermal weapons were used in warfare during the classical and medieval periods using heat or burning action to destroy or damage enemy personnel, fortifications or territories.

Industrial warfare

Industrial warfare is a period in the history of warfare ranging roughly from the early 19th century and the start of the Industrial Revolution to the beginning of the Atomic Age, which saw the rise of nation-states, capable of creating and equipping large armies, navies, and air forces, through the process of industrialisation.

The following outline is provided as an overview of and topical guide to military science:

Underwater firearm Firearms that can be effectively fired underwater

An underwater firearm is a firearm designed for use underwater. They are in the arms inventories of many nations. A common feature of underwater firearms or needleguns is that they fire flechettes or spear-like bolts instead of standard bullets. These may be fired by pressurised gas.

Ammunition Weapon loads: projectiles, bombs, missiles

Ammunition is the material fired, scattered, dropped or detonated from any weapon. Ammunition is both expendable weapons and the component parts of other weapons that create the effect on a target. Nearly all mechanical weapons require some form of ammunition to operate.

Gun weapon designed to discharge projectiles or other material

A gun is a ranged weapon designed to use a shooting tube to launch typically solid projectiles, but can also project pressurized liquid, gas or even charged particles. Solid projectiles may be free-flying or tethered. A large-caliber gun is also referred to as a cannon.

History of weapons aspect of history

People have used weapons in warfare, hunting, self-defense, law enforcement, and criminal activity. Weapons also serve many other purposes in society including use in sports, collections for display, and historical displays and demonstrations. As technology has developed throughout history, weapons have changed with it.

Chemical weapon Device that uses chemicals to harm or kill people

A chemical weapon (CW) is a specialized munition that uses chemicals formulated to inflict death or harm on humans. According to the Organisation for the Prohibition of Chemical Weapons (OPCW), "the term chemical weapon may also be applied to any toxic chemical or its precursor that can cause death, injury, temporary incapacitation or sensory irritation through its chemical action. Munitions or other delivery devices designed to deliver chemical weapons, whether filled or unfilled, are also considered weapons themselves."

Egypt and weapons of mass destruction

Egypt had a history of weapons of mass destruction and used chemical weapons during the North Yemen Civil War. Although it has signed the Nuclear Non-Proliferation Treaty, it still remains one of only four countries not to ratify the Chemical Weapons Convention and has not ratified the Biological Weapons Convention.


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