Some light up keyboards have some additional functionality features. Red is a common choice of backlighting, since it is easy on the eyes in the dark, but blue, purple, green, white, and other colors can be used, with some keyboards having several color options for users to choose from. The characters on the keys may be transparent so that they also glow when the keyboard is illuminated. Many light up keyboards are simply backlit, with an array of lights which illuminate the area behind the keys, causing the outlines around the keys to light up. Computer gamers are especially fond of light up keyboards, some of which are specifically optimized for gaming, and these keyboards are also used by people on board ships and aircraft, and biologists who want to record data in dark environments without turning a light on and disturbing their subjects.īack-lit keyboards are a standard feature on Apple's MacBook line. These keyboards are designed for use by people who work in dark environments to increase accuracy and to make it easier to use the keyboard. A light up keyboard is a keyboard which can be illuminated during use.