What does CMYK mean?

The CMYK color profile is the current standard color model for four-color printing.

It delivers outstanding color results for printed materials and is based on the three primary colors Cyan, Magenta, and Yellow, complemented by Black, which is referred to as Key or Key Colour. The term "Key" refers to the black key plate used in printing, which serves as the alignment for the other three colors. The abbreviation CMYK is derived from these primary colors and the key color.