Paintball is a sport in which participants eliminate opponents from play by hitting them with paintballs (spherical gelatin capsules containing primarily polyethylene glycol, other non-toxic and water-soluble substances, and dye) shot from a compressed-gas-powered "marker".

Paintball draws a wide array of players, and the Sporting Goods Manufacturer's Association estimates that over 10 million people play annually in the United States alone. Insurance statistics show that paintball is one of the safest sports in existence, even more so than tennis.

Games can be played either indoors or outdoors and take various forms, of which some of the most popular are woodsball, scenario and speedball, also sometimes known as tourneyball under various circumstances. Rules for playing paintball vary widely, with most designed to ensure that participants enjoy the sport in a safe environment. The sport requires a significant amount of equipment and has even developed its own slang.

A game of paintball usually involves two opposing teams seeking to eliminate all of the other team's players or to complete an objective, such as retrieving a flag, eliminating a specific player, or other paintball variations. An average, non-professional game of paintball usually lasts around five minutes to half an hour. Since its inception, paintball has drawn a crowd of both casual and serious players.