Color complementary wheel diagram

Quick answer：

The complementary color wheel is a color model that pairs colors which, when combined, cancel each other out to form a gray or white color. It is a tool used in art, design, and graphic design to understand color relationships. In the color wheel, complementary colors are opposite each other, such as red and green, blue and orange, and yellow and purple. This concept is based on the additive color model used in color printing and television technology.