The RGB color space

The RGB color space is the best-known and most widely used color model. In RGB each color is represented by 3 values red ( R ), green ( G ) and blue ( B ), positioned along the axes of the Cartesian coordinate system.  The values of RGB are assumed to be in the range of [0,1] or in some cases in the range of [0-255]. This way black is represented as (0, 0, 0), white is represented as (1, 1, 1) or (255, 255, 255). These black and the white colors are represented by 2 of the opposite corner of the cube that can be defined by the R, G, B axes of the Cartesian coordinate systems. Other corners of the cube represent the red, green, blue, cyan, magenta and yellow colors. Grayscale colors are represented with identical R, G, B components.

Because the RGB color space is widely used in monitors, digital cameras, it is the most important color space in image processing.