CMYK stands for the four printing inks Cyan, Magenta, Yellow and “Key” (Black) . These four inks are the base of four-color printing. For printing colorful photos at least these four inks are required.

CMYK color spaces depend on the printer and the paper used and therefore need color profiles to describe the exact shades.

The main CMYK color spaces are:

ISOcoatedv2
PSOUncoated
GRACol
SWOP