Tertiary color secondary colors: orange-green, green-purple, purple-orange; or by intermixing complementary colors. This approach to tertiary color relates specifically to color in the form of paints, pigments and dyes. The primary colors in an RGB color wheel are red, green, and blue, because these are the three additive colors—the primary colors of light. The secondary colors in an RGB color wheel are cyan, magenta, and yellow because these are the three subtractive colors—the primary colors of pigment. The tertiary color names used in the descriptions of RGB (or equivalently CMYK) systems are shown below. The primary colors in an RYB color wheel
Color printing are variously used in printing, the result should be a reasonable reproduction of the original, but in practice this is not the case. Due to limitations in the inks, the darker colors are dirty and muddied. To resolve this, a black separation is also created, which improves the shadow and contrast of the image. Numerous techniques exist to derive this black separation from the original image; these include grey component replacement, under color removal, and under color addition. This printing technique is referred to as CMYK (the "K" stands for "key", a traditional word for the black printing plate). Today's