Starting with the Numbers
Four Color printing simply means the four primary colors of cyan, magenta, yellow and black (CMYK) are used to produce all the colors you normally see in print magazines, posters, banners, and books. Colors are one of the key pieces to printing. If you are going to print in full color, in the printing world you'll denote this by using the number "4". If you're going to print with black and white, you'll denote this using the number "1". If you want no printing on one side of the document, you'll denote this using the number "0".
So putting it all together here is what each combination of numbers mean:
- 4:0 - Full color on one side, blank on the other
- 4:1 - Full color on one side, black and white on the back
- 4:4 - Full color on both sides
CMYK vs. RGB
CMYK as indicated above is also known as four color printing using the four colors: cyan, magenta, yellow and black to produce all colors seen on print. This is different from RGB Color: red, green, blue. RGB is generally what you will see on your monitor. The colors are designated to the three regions of green, red and blue. These regions produce the variety of colors that you then see on your computer screen. If the printing project is done on your computer, one thing the printer will do is translate the RGB colors into CMYK format. In order to do this, the primary colors (cyan, magenta, and yellow) are taken and mixed with black. This gives the variety of colors and hues necessary for your job.
Black & White vs. Color Costs
Black & white jobs use less resources to get the same color job done; however, that's not to say that color printing is not cost effective. The cost of color printing has come down dramatically over the years and depending on where you go you should be able to get color printing for similar costs or just a little higher costs than black & white printing.