According to Apple Inc., the RGB signal is the standard signal for most computer graphics and video files. It is named for the colors red, green and blue. These colors, in certain combinations and intensities, can create any other color. RGB also supports grayscale, ranging from black to white.
Despite its popular usage, RGB is not represented in the same method across devices. Different devices have unique mechanisms of formulating RGB. This is one reason that color management is available to the user, to rectify perceived color abnormalities. The concept behind RGB existed before the advent of television and computer technology, dating back to the 19th century.