April 19, 2011, 11:17 p.m.
posted by r11
While RGB (Red, Green, Blue) is the color standard for the Web, CMYK (Cyan, Magenta, Yellow and Key [or Black]) is the standard in print. The CMYK color scheme is based on pigment (a substance used as coloring), and how light is reflected off each pigment. When working with the CMYK color scheme, you can create black by adding the maximum values of cyan, magenta, and yellow. Different levels of gray can be created by combining equal, but not maximum, amounts of cyan, magenta, and yellow. White is simply the absence of all color (so the white page shows through). Most color printers you find today work using the CMYK color model and can simulate almost any color by printing two colors very close to each other.
For more information about using the RGB and CMYK color modes in the Adobe Create Suite, see Chapter 7 of this minibook.