Subtractive colour mixing: CMYK inks

Subtractive colour mixing: CMYK. Image showing printing inks being poured onto paper. Yellow, magenta, and cyan inks spread and overlap to create the subtractive secondary colours (red, green, and blue). Where all three inks overlap the result is black. This type of colour mixing (using pigments) is the basis for colour printing. However, they generally also use black ink (the K in CMYK) since it is more efficient than relying on the three basic inks. This is known as four colour printing.