What Does "K" Stand for in CMYK?
CMYK, also known as four color process, is the standard in the printing industry for reproducing full color images. CMYK stands for Cyan, Magenta, Yellow and Black, the colors used in four color process printing. So this begs the question - why is it not called CMYB?
Well the answer is two-fold. Back in the old days of printing when all printing was done using plates the black plate was actually called the Key plate. This was because it contained the artistic detail or "key" information. Look at the pictures below and to the left (courtesy of Wikipedia) that show the breakdown of a photo into the components of CMYK. You can see that the most detail is in the black color - hence the name for the black plate being the Key plate.
The second reason has to do with avoiding confusion with another very popular color model - RGB. RGB stands for Red-Green-Blue and this is how computer monitors and televisions represent color. Even though no one refers to the Black plate as the Key plate anymore, to avoid confusion with the RGB model, the four color process model has remained as CMYK.









