The perception of the different wavelengths of light. It is possible to create almost all visible colors using two systems of primary colors. Transmitted colors use red, green and blue (RGB), and reflected colors use cyan (light blue), magenta (purplish-red), yellow and black (CMYK). Color displays use RGB (colors are added to create white) and color printing uses CMYK (colors are subtracted to create white).|
The two major ways to create colors are RGB and CMY. RGB uses red, green and blue pixels for the display screen. CMY uses cyan, magenta and yellow inks to print on paper. In theory, equal parts of cyan, magenta and yellow ink make black, but the blacks tend to be muddy. Thus, a pure black fourth ink is always used in the four color CMYK process (K for blacK).