Projected color or color on a screen is produced through the additive color model, using red,green, and blue (RGB) light. Every pixel on a screen consists of tiny subpixels that emit these three colors. 

Color in print works through a process called subtractive color mixing. This involves the use of the CMYK color model which stands for Cyan, Magenta, Yellow, and Key (Black).

These are two different and important ways in which color can be demostrated on various technologies.