Weapon

A weapon is an instrument used for the purpose of causing harm or damage to persons, animals or structures. Weapons are used in hunting, attack, self-defense, or defense in combat and range from simple implements like clubs and spears to complicated modern machines such as intercontinental ballistic missiles. One who possesses or carries a weapon is said to be armed.

In a broader context weapons include anything used to gain an advantage over an adversary or to place them at a disadvantage. Examples include the use of sieges, tactics, and psychological weapons which reduce the morale of an enemy.

Prehistoric
Very simple weapon use has been observed among chimpanzees, leading to speculation that early hominids began their first use of weapons as early as five million years ago. These would have been wooden clubs, spears, and unshaped stones&mdash;none of which would leave an unambiguous record.

The earliest unambiguous weapons are:
 * Eight wooden throwing spears, the Schöninger Speere, dated to around 400,000 years old.
 * By 250,000 years ago wooden spears were made with fire-hardened points
 * The oldest atlatl dates back to 27,000 years ago.
 * Throwing sticks are also some of the earliest types of weapons.

Ancient and classical
Ancient weapons were evolutionary improvements of late neolithic implements, but then significant improvements in materials and crafting techniques created a series of revolutions in military technology:

The development of metal tools, beginning with copper during the Copper Age (about 3,300 BC) and followed shortly by bronze led to the Bronze Age sword and similar weapons.

The first defensive structures and fortifications appeared in the Bronze Age. Indicating an increased need for security. Weapons designed to breach fortifications followed soon after, for example the battering ram was in use by 2500 BC.

Although early Iron Age swords were not superior to their bronze predecessors, once iron-working developed - around 1200 BC in Sub-Saharan Africa, iron began to be used widely in weapon production because iron ore was much more readily available than the copper and tin required to create bronze.

Cavalry developed once horses were bred to support the weight of a man. The horse extended the range and increased the speed of attack, but was not a weapon as much as it provided an enhanced capability.

Domestication of the horse and widespread use of spoked wheels by ca. 2000 BC, led to the light, horse-drawn chariot. The mobility provided by chariots were important during this era. Spoke-wheeled chariot usage peaked around 1300 BC and then declined, ceasing to be militarily relevant by the 4th century BC.

Ships built as weapons or warships such as the Triremes were in use by the 7th century BC. These ships were eventually replaced by larger ships by the 4th century BC.

Tactics and organization
As technology advanced, so did the level of organization of peoples eventually leading to the development of empires and armies. Professional armies allowed aggressive, militaristic states to emerge.

While early Greek armies focused on physical training and individual ability, a key advancement of the Roman army was the development complex tactics used to gain additional advantage over their enemies.

Middle Ages
European warfare during the middle ages 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. Whereas 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 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 Far East 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.

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 various technologies including the machine gun and ironclad warship emerged that would 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 age of edged weapons ended abruptly just before World War I with rifled artillery. Howitzers were able to destroy masonry fortresses and other fortifications. This single invention caused a Revolution in Military Affairs (RMA) and established tactics and doctrine that are still in use today. See Technology during World War I for a detailed discussion.

An important feature of industrial age warfare was technological escalation - innovations were rapidly matched through replication or countered by yet another innovation. The technological escalation during World War I (WW I) was profound, producing armed aircraft and tanks.

This continued in the inter-war period (between WW I and WW II) with continuous evolution of all weapon systems by all major industrial powers. 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.

Modern
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", 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, the tank and above all the wide introduction of aircraft into warfare, including naval warfare with the introduction of the aircraft carriers.

World War I marked the entry of fully industrialized warfare as well as weapons of mass destruction (e.g. chemical and biological), and 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.

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 more weapons influenced the world in different ways.

Since World War II
After World War II and with the onset of the Cold War, constant technological advancement of weapons was institutionalized. Countries engaged in a competitive race to develop more lethal weapons and counter-weapons. This arms race has continued into the current era and remains a drain on the resources of most nations.

Notable development in weaponry since World War II has been the combination and further development of nuclear weapons and ballistic missiles. Resulting in the development of the intercontinental ballistic missile (ICBM). The Cold War race for larger and more effective weapons lead to the refinement of the atomic weapons (hydrogen bomb) and multiple warhead missiles. The mutual possession of ICBMs by the United States and the Soviet Union created an environment of mutually assured destruction (see below). The indiscriminate nature of the destruction has made nuclear-tipped missiles essentially useless for the smaller wars fought since.

However computer-guided weaponry of all kinds, from precision-guided munitions (or "smart bombs") to computer-aimed tank rounds, have greatly increased weaponry's accuracy. Being able to prepare, maneuver and attack before the enemy can detect the threat and respond can provide a decisive advantage. The element of surprise has long been recognized as a tactical advantage. Modern technology has increased this though sophisticated night vision technology allowing maneuvering and engagement at night when the enemy, not as well equipped, has limited visibility. Advanced technological surveillance and intelligence gathering methods through the use of unmanned aerial vehicles is a benefit to prevent surprise and identify targets.

Coordination of forces is necessary in order to control disparate forces effectively. Modern communications, if unjammed and not intercepted are a substantial advantage. Once targets or strategic objectives are identified it is necessary to prepare detailed plans for individual forces to follow. This can be a time consuming process that modern armies are using computers to overcome. Successful integration of automated planning can result in more responsive use of existing weapons platforms against the enemy.

Cyberwarfare is an emerging weapon that recognizes the vulnerabilities of enemy infrastructure, intelligence apparatus, and communications systems and provides from their disruption.

Nuclear age and beyond
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 former Soviet Union engaged in a nuclear arms race. Each country and their allied blocks 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 entire planet (see Mutually Assured Destruction) 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 nuclear war.

By user

 * - what person or unit uses the weapon


 * Personal weapons (or small arms) - designed to be used by a single person.
 * Hunting weapon - primarily for hunting game animals for food or sport
 * Infantry support weapons - larger than personal weapons, requiring two or more to operate correctly.
 * Fortification weapons - mounted in a permanent installation, or used primarily within a fortification.
 * Mountain weapons - for use by mountain forces or those operating in difficult terrain.
 * Vehicle weapons - to be mounted on any type of military vehicle.
 * Railway weapons - designed to be mounted on railway cars, including armored trains.
 * Aircraft weapons - carried on and used by some type of aircraft, helicopter, or other aerial vehicle.
 * Naval weapons - mounted on ships and submarines.
 * Space weapons - are designed to be used in or launched from space.

By function

 * - the construction of the weapon and principle of operation


 * Antimatter weapons (theoretical) would combine matter and antimatter to cause a powerful explosion.
 * Archery weapons operate by using a tensioned string to launch a projectile.
 * Artillery are capable of launching heavy projectiles over long distances.
 * Biological weapons spread biological agents, causing disease or infection.
 * Chemical weapons, poisoning and causing reactions.
 * Energy weapons rely on concentrating forms of energy to attack, such as lasers or sonic attack.
 * Explosive weapons use a physical explosion to create blast concussion or spread shrapnel.
 * Firearms use a chemical charge to launch projectiles.
 * Improvised weapons are common objects, reused as weapons.
 * Incendiary weapons cause damage by fire.
 * Non-lethal weapons are designed to subdue without killing.
 * Magnetic weapons use magnetic fields to propel projectiles, or to focus particle beams.
 * Mêlée weapons operate as physical extensions of the user's body and directly impact their target.
 * Missiles are rockets which are guided to their target after launch. (Also a general term for projectile weapons).
 * Nuclear weapons use radioactive materials to create nuclear fission and/or nuclear fusion detonations.
 * Primitive weapons make little or no use of technological or industrial elements.
 * Ranged weapons (unlike Mêlée weapons), target a distant object or person.
 * Rockets use chemical propellant to accelerate a projectile
 * Suicide weapons exploit the willingness of their operator to not survive the attack.
 * Trojan weapons appear on face value to be gifts, though the intent is to in some way to harm the recipient.

By target

 * ''- the type of target the weapon is designed to attack


 * Anti-aircraft weapons target missiles and aerial vehicles in flight.
 * Anti-fortification weapons are designed to target enemy installations.
 * Anti-personnel weapons are designed to attack people, either individually or in numbers.
 * Anti-radiation weapons target sources of electronic radiation, particularly radar emitters.
 * Anti-satellite weapons target orbiting satellites.
 * Anti-ship weapons target ships and vessels on water.
 * Anti-submarine weapons target submarines and other underwater targets.
 * Anti-tank weapons are designed to defeat armored targets.
 * Area denial weapons target territory, making it unsafe or unsuitable for enemy use or travel.
 * Hunting weapons are civilian weapons used to hunt animals.
 * Infantry support weapons are designed to attack various threats to infantry units.