Color is the sensation produced in response to selective absorption of wavelengths from visible light. It possesses the attributes of Brightness, Saturation and Hue. An international standard developed by CIE can be used for measurement of these attributes for any colour.
CIE L*a*b* is perhaps the most accurate representation of color and is typically used internally by color management software to transition colors from one color space (e.g. RGB) into another (e.g. CMYK).