The color wheel arranges hues in a circle to show their relationships. Isaac Newton is often credited with the first circular diagram in 1666, though earlier thinkers had explored similar ideas. The wheel has taken many forms since. Some versions place red, yellow, and blue at equal points, based on traditional painting. Others use cyan, magenta, and yellow for printing, or red, green, and blue for light. Each wheel reflects a different mixing system.

Designers use the wheel to build palettes. Colors opposite each other are complementary and create strong contrast. Colors next to each other are analogous and harmonize. Colors at the points of an equilateral triangle form a triadic scheme. Split-complementary uses a base color and the two colors adjacent to its complement. These patterns are starting points, not formulas. A palette that looks balanced on the wheel may fail in context, depending on lighting, material, and cultural associations.

Common color relationships

• Complementary: opposite on the wheel.
• Analogous: adjacent on the wheel.
• Triadic: three evenly spaced colors.
• Split-complementary: base plus two near-complements.

The color wheel is a map, not a territory. It helps designers see relationships, but the final judgment happens in the work itself.