When it comes to adding a splash of color to your work, there are two important distinctions to make depending on where they are intended to be displayed.
In basic terms, RGB is a color mode intended for use in the digital space. Essentially, it covers everything that is displayed on a screen. CMYK on the other hand, is for anything printed, such as newspapers, posters or business cards.
The term RGB stands for the names of the primary colors, Red Green and Blue. Everything you see on a screen is created by combining various percentages of these three colors via the pixels that make up a display. Within each pixel are sub-pixels split into the three colors that display light accordingly to create color.
The value of each color in the RGB mode can be in the range 0-255. When all three values are 0, the color is black, and on the other end of the spectrum, to create white the values are all set to 255. This means that there are over 16 million possible color combinations in between!
CMYK, on the other hand, stands for the four colors Cyan, Magenta, Yellow and Black. The ‘B’ in this case is already used by RGB so instead takes the ‘K’ from the last letter of the color’s name instead. Rather than RGB which adds color together, CYMK is subtractive, due to physical ink ‘subtracting’ color from white light.
CMYK values are measured in percentages, meaning the range of color is 4x100. With fewer combinations available, it means that print outputs are easier to standardize, however there is no way near the range that RBG is able to create on screens. This can lead to color variations between digital and printed products.
Knowing the difference is important to provide a better understanding of the printing process and how that affects the work you are wanting to create.