Why do artists use a color wheel?
Rainbow Pizza Map
Why do artists use a color wheel?

You've probably seen one pinned to an art room wall — a circle sliced into rainbow wedges like the world's most colorful pizza. It's called a color wheel, and artists treat it like a cheat sheet for making colors play nicely together. But why a wheel? Why not a list, or a grid, or a blob?
Start with the three colors you can't make by mixing: red, yellow, and blue. Artists call these the primary colors. They're the building blocks — like the flour, sugar, and butter of the color world. Everything else comes from them.
