This is a question we get a lot here at Spartan. What is the difference between CMYK and RGB, and why does it matter? It gets even more confusing when you bring Spot colors into the mix.
To start with, CMYK stands for Cyan, Magenta, Yellow, and Key. Key? What color is “Key”? Well, in a nutshell, it’s black. The other three ink color plates are keyed to the black plate, hence the name. RGB stands for Red, Green, and Blue. The key difference between CMYK and RGB is how they function. As you add the four CMYK ink colors together, you get progressively darker and darker colors until you end up with black. CMYK is based on pigments. RGB, by contrast, is based on light. If you add all three colors together, you get pure white. In effect, CMYK and RGB are foils to eachother. CYMK is also referred to as process, or 4-color process.