RYB color model as the "three" psychological primaries, with black and white occasionally added as a fourth and fifth. The cyan, magenta, and yellow primary colors associated with CMYK printing are sometimes known as "process blue", "process red" and "process yellow". RYB color model RYB (an abbreviation of red–yellow–blue) is a historical set of colors used in subtractive color mixing and is one commonly used set of primary colors. It is primarily used in art and design education, particularly painting. RYB predates modern scientific color theory, which has determined that cyan, magenta, and yellow are the best set of three colorants to combine,
Subtractive color the spectrum. Magenta is the complement of green, and yellow the complement of blue. Combinations of different amounts of the three can produce a wide range of colors with good saturation. In inkjet color printing and typical mass production photomechanical printing processes, a black ink K (Key) component is included, resulting in the CMYK color model. The black ink serves to cover unwanted tints in dark areas of the printed image, which result from the imperfect transparency of commercially practical CMY inks; to improve image sharpness, which tends to be degraded by imperfect registration of the three color elements; and