Primary colors are sets of
colors that can be combined to make a useful range (
gamut) of colors. For human applications, three are often used; for additive combination of colors, as in overlapping projected lights or in
CRT displays, the primary colors normally used are
red,
green, and
blue. For subtractive combination of colors, as in mixing of pigments or dyes, such as in printing, the primaries normally used are
magenta,
cyan, and
yellow.
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