A short story about RGB & CMYK
This is not a science lesson about color, these are just the facts in Plain English.
RGB (Red, Green and Blue) is for screens: computer monitors, phones, TVs and cameras. It uses light to create images.
CMYK (Cyan, Magenta, Yellow and Black) is for printing: anything on paper, cloth and advertising specialties. CMYK uses ink to create images.
For the most part, you can design in RGB and just export CMYK for printing and RGB for the web. Let’s say you have a campaign that includes a Facebook post, an Instagram post, a LinkedIn post, an eBlast, a postcard and a printed invitation. You don’t need to have separate versions of your support files for screen and for print. You can export a PDF for print with CMYK settings and export a JPG or PNG for screens with RGB settings. Most of the time, this works out just fine.
When does it not work? If you have a color that is outside of the CMYK gamut, you may have a surprise when it’s time to print. Unfortunately, the CMYK gamut is smaller than the RGB gamut, but that’s science.
See the example below of a brilliantly colored RGB photo that loses its magic when converted to CMYK.
How to avoid this? Understand the limitations of CMYK vs RGB before designing. If you have an image with very vibrant colors, it’s best to convert it to CMYK just to see what will happen when it goes to press with Cyan, Magenta, Yellow and Black inks.