It is the difference between additive mixing and subtractive mixing. When you mix colors on a screen with RGB, you add light. When you mix pigments on a physical medium, you subtract the amount of light reflected (because each paint absorbs most light except the colors it reflects, which are what you see).
As a side note, when mixing in the subtractive color system, your primary colors are cyan, magenta, and yellow. That’s why a printer takes CMYK, for cyan, magenta, yellow, and black. In case you were wondering, ‘K’ here is black.
It is the difference between additive mixing and subtractive mixing. When you mix colors on a screen with RGB, you add light. When you mix pigments on a physical medium, you subtract the amount of light reflected (because each paint absorbs most light except the colors it reflects, which are what you see).
As a side note, when mixing in the subtractive color system, your primary colors are cyan, magenta, and yellow. That’s why a printer takes CMYK, for cyan, magenta, yellow, and black. In case you were wondering, ‘K’ here is black.