Which color is not classified as a primary color?

In color theory, primary colors are the foundational colors that cannot be created by mixing other colors together. In traditional color theory, particularly in the context of art and design, the primary colors are yellow, red, and blue. These colors can be combined in various ways to create a broad spectrum of other colors.

Green, on the other hand, is derived from the combination of two primary colors: blue and yellow. Therefore, it does not hold the status of a primary color. Understanding this basic principle is crucial for anyone studying color in relation to design, art, or even hairstyling, as it serves as the building block for all subsequent color mixing and application.