The practice of specifying or creating colors using three stimuli. These may be additive (RGB) or subtractive (CMY) primary colorants; three attributes such as Lightness, Chroma, and Hue; or three purely synthetic mathematical constructs, as with CIE XYZ (1931) or CIELAB.
A three-valued signal that can match nearly all colors of visible light in human vision. This is possible because of the three types of photoreceptors in the eye. RGB, YC, and similar signals are tristimulus, and can be interchanged by using mathematical transformations (subject to possible loss of information).
A method for communicating or generating a color using three stimuli – either additive or subtractive colorants (such as RGB or CMY), or three attributes (such as lightness, chroma, and hue).