Paintball is a sport in which players compete, in teams or individually, to eliminate opponents by hitting them with capsules containing food coloring and gelatin (referred to as paintballs) propelled from a gun called a paintball marker. Paintballs have a non-toxic, biodegradable, water soluble mineral-oil.

Games are played on indoor or outdoor fields of varying sizes. A game field is scattered with natural or artificial terrain, which players use for strategic play.

Rules for playing paintball vary, but can include capture the flag, elimination, defending or attacking a particular point or area, or capturing objects of interest hidden in the playing area. Depending on the variant played, games can last from seconds to hours, or even days in scenario play.

Source: Wikipedia