Light gun shooter, also called light gun game or simply gun game, is a shooter video game genre in which the primary design element is aiming and shooting with a gun-shaped controller. Light gun shooters revolve around the protagonist shooting targets, either antagonists or inanimate objects. Light gun shooters generally feature action or horror themes and some may employ a humorous, parodic treatment of these conventions. These games typically feature "on-rails" movement, which gives the player control only over aiming; the protagonist's other movements are determined by the game. Games featuring this device are sometimes termed "rail shooters", though this term is also applied to games of other genres in which "on-rails" movement is a feature. Some, particularly later, games give the player greater control over movement and in still others the protagonist does not move at all.