Paintball is a competitive team shooting sport in which players eliminate opponents from play by hitting them with spherical dye-filled gelatin capsules ("paintballs") that break upon impact. Paintballs are usually shot using a low-energy air weapon called a paintball marker that is powered by compressed air (nitrogen) or carbon dioxide and was originally designed for remotely marking trees and cattle.

The game was initially developed in May 1981 for recreation but now is frequently played at a formal sporting level with an organized competition that involves major tournaments, professional teams, and players. Paintball technology is also used by military forces, law enforcement, paramilitary and security organizations to supplement military or other training. Paintball markers can play a role in riot response and nonlethal suppression of dangerous suspects.

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