The color wheel or color circle is the basic tool for combining colors. The first circular color diagram was designed by Sir Isaac Newton in 1666.
The color wheel is designed so that virtually any colors you pick from it will look good together. Over the years, many variations of the basic design have been made, but the most common version is a wheel of 12 colors based on the RYB (or artistic) color model.
Traditionally, there are a number of color combinations that are considered especially pleasing. These are called color harmonies or color chords and they consist of two or more colors with a fixed relation in the color wheel.