analogous colour schemes use colours that are next to each other on the wheel. (for example: light blue, dark green and light green)

a triadic colour scheme uses colours that are evenly spaced around the colour wheel (for example: purple, orange and green)

the split complementary colour scheme is a variation of complementary colours adding to the base colour, it uses the two colours adjacent to its complement

the square and rectangle colour schemes use four colours arranged into two complementary pairs, the difference being the square uses colours evenly spread around the wheel