Contrary to popular belief, this is not referring to, say, a six shooter that weighs less (Nor does it have fewer calories, as Luke's mom is stupid enough to believe). Or a laser
An alternative style of videogame controller, shaped like a gun. Pulling the trigger would cause the game to register a shot at whatever the gun was aimed at. Light Gun Games were invariably some form of marksmanship simulator.
Though the name and illustrations suggest that the controller fires some sort of energy beam at the screen, a Light Gun does not actually fire anything: its barrel contains a small camera, which senses hidden marks in the game's display and uses these to fix its position. This tracking data mostly relies on the blanking interval and interlaced scan of the CRT display. Thus, a traditional light gun is incompatible with any LCD or other advanced display, or even rear-projection CRTs. New systems compatible with advanced displays use either a similar mechanism that requires an orientation target near the screen (typically an infrared light source), or an accelerometer inside the controller, which detects the direction and speed of movement. The Nintendo Wii Remote uses both and can detect a huge range of motion, orientation, and position via dead reckoning.
The Nintendo Entertainment System was available with the "Zapper" light gun, which was supported by several games. The Super Nintendo eventually featured its own light gun, the Super Scope, modeled on a bazooka. The GunCon and GunCon 2 later were prominent on the PlayStation and PlayStation 2, and the Wii seems to be making its own appearance of gun peripherals.
Though similar, arcade games where the gun is physically mounted on the machine (rather than being attached by a cable) are not technically Light Guns, but rather a normal joystick with an exotic shape. Silent Scope is one of these games, with an extra distinguishing feature-an actual display in the scope for a zoomed-in view.
If the player moves at all in a Light Gun Game, his movement will generally follow an Invisible Grid, either moving automatically when there is nothing nearby to shoot at, or advancing in response to a button on a second controller. This style of game is called a Rail Shooter.
The Wii is an ideal system for porting light gun games to or releasing original light gun games, as the Wii already comes with a light gun of sorts—the Wii Remote and its pointer functionality. If you want a more arcade-like experience, you can also buy gun shells such as the Wii Zapper and Nyko Perfect Shot. If you do buy one, don't tell anybody that you did.