The CMYK Model

Needlesss to say there is nothing fundamental about the primary colors red, green and blue. One could just as easily treat the other set of three dominant colors, cyan, magenta and yellow as an alternate set of primary colors. This forms the basis of the color model used extensively in the printing industry.

Printed materials, as indeed most colored materials in nature, do not emit any light. The colors we perceive are the result of the way in which they selectively reflect light. Thus coating a white paper with cyan and magenta would result in only blue light being reflected with the result that the paper would appear blue. In theory one can completely block reflection of light by the white surface by using successive coatings in Cyan, Magenta and Yellow. In practice it is cheaper and more reliable to use a separate blacK. Hence the name CMYK. Individual colors in this model are expressed either as a percentage or as a fraction.