the visual perceptual property corresponding in humans to the categories called red, green, blue and others
Color is the visual perceptual property corresponding in humans to the categories called red, green, blue and others. Color derives from the spectrum of light (distribution of light energy versus wavelength) interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical specifications of color are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra.
Reference: Wikipedia article about 'Color', retrieved 2011-04-25
