Light gun shooter  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. Light gun shooters employ "light gun" controllers, so named because they function through the use of light sensors. Mechanical games using light guns had existed since the 1930s, though they operated differently from those used in video games. Throughout the 1970s mechanical games were replaced by electronic video games and in the 1980s popular light gun shooters such as "Duck Hunt" emerged. The genre was most popular in the 1990s, subsequent to the release of "Virtua Cop," the formula of which was later improved upon by "Time Crisis". The genre is less popular in the new millennium, as well as being hampered by compatibility issues, but retains a niche appeal for fans of "old school" gameplay. "Light gun shooters", "light gun games" or "gun games" are games in which the protagonist shoots at targets, whether antagonists or objects, and which use a gun-shaped controller (termed a "light gun") with which the player aims. While light gun games may feature a first-person perspective, they are distinct from first person shooters, which use more conventional input devices. Light gun games which feature "on-rails" movement are sometimes termed "rail shooters", though this term is also applied to other types of shooters featuring similar movement. The light gun itself is so termed because it functions through the use of a light sensor: pulling the trigger allows it to detect light from the on-screen targets. Targets in light gun shooters may be threatening antagonists such as criminals, terrorists or zombies, or they may be inanimate objects such as apples or bottles. Although these games may be played without a light gun, the use of more conventional input methods has been deemed inferior.