The 12-color wheel's adjacent colors

Quick answer：

The 12-color wheel, also known as the Munsell color system, is a color model that divides colors into three categories: hues, values, and chromas. Adjacent colors on the 12-color wheel are those that are next to each other. They share the same hue but differ in value or chroma. For example, adjacent colors to red are red-orange or red-violet. This concept is essential in art and design for understanding color relationships and harmonies.