complementary colors are colors directly opposite each other on the color wheel.

analogous colors are 3 colors next to each other on the color wheel.

triadic color schemes use colors that are evenly spaced out on the color wheel.

split-complementary uses a base color and the two colors adjacent to its complement.

rectangular tetrad colour scheme uses four colors arranged into two complementary pairs.

square colour scheme uses four colors that are spaced evenly around the color wheel.