Wikipedia
Color printing or colour printing is the reproduction of an image or text in color (as opposed to simpler black and white or monochrome printing). Any natural scene or color photograph can be optically and physiologically dissected into three primary colors, red, green and blue, roughly equal amounts of which give rise to the perception of white, and different proportions of which give rise to the visual sensations of all other colors. The additive combination of any two primary colors in roughly equal proportion gives rise to the perception of a secondary color. For example, red and green yields yellow, red and blue yields magenta (a purple hue), and green and blue yield cyan (a turquoise hue). Only yellow is counter-intuitive. Yellow, cyan and magenta are merely the "basic" secondary colors: unequal mixtures of the primaries give rise to perception of many other colors all of which may be considered " tertiary."
Usage examples of "color printing".
Apart from trifles like sharp focus and the best length and brightness of exposure, there was the matter of color itself, which came out differently on each make of film, and on each type of photographic printing paper, and even on paper from two boxes of the same type from the same manufacturer: the reason for this being that the four ultra-thin layers of emulsion laid onto color printing paper varied slightly from batch to batch.
In garish four-color printing, a boatload of heroic Malay pirates gallantly advanced on a sinister Portuguese galleon.