Weapon

A weapon is any tool used to harm, kill, destroy property, or intimidate another person. It may be hand-held, such as a knife or club, or technologically sophisticated, such as a gun, cannon, or missile. Objects originally made for other purposes—such as an axe or stone—can become weapons when used as such.

Weapons are used for hunting, self-defense, law enforcement, military conflict, and crime. Governments typically regulate who may possess certain types of weapons, how they may be transported within and outside the country, and where they may be carried. International treaties also restrict or limit certain categories of weapons.

General categories

The conventional classification divides weapons into two broad types. Melee weapons require the user to be close to the target; examples include knives, swords, and spears. Ranged weapons can strike targets at a distance; examples include bows, guns, cannons, and missiles. A third category commonly recognized is explosive weapons, such as grenades and mines.

Weapons of mass destruction

The term "weapons of mass destruction" refers to nuclear, chemical, and biological weapons. They differ from conventional weapons in that a single use can affect large populations and wide areas, and combatants cannot easily be distinguished from civilians. International treaties—including those on preventing the spread of nuclear weapons, prohibiting chemical weapons, and prohibiting biological weapons—govern the production, storage, and use of these types.

Brief history

The earliest weapons consisted of stone, spears, and clubs; later, polished metal was added, leading to swords and harder weapons. The invention of gunpowder introduced firearms and cannons, which transformed warfare. In the nineteenth and twentieth centuries, industrialization and technology produced rapid-fire weapons, military aircraft, long-range missiles, and nuclear weapons. In the modern era, electronic systems, unmanned aircraft (drones), and computer-guided equipment play a major role.

Law and regulation

International humanitarian law sets limits on how weapons may be used during armed conflict: the goal is to distinguish combatants from civilians and prevent unnecessary suffering. Certain weapons are also banned by treaty, such as anti-personnel mines and incendiary weapons when used against civilians. At the national level, firearms law varies by country: some require licensing and registration, while others prohibit certain categories of weapons from civilian ownership entirely.