What is the primary purpose of hue in color perception?

Hue is fundamental in color perception as it refers to the attribute of a color that allows us to categorize it and identify it as red, blue, green, or any other specific color. This means hue is essentially about recognizing and labeling colors based on their specific wavelengths of light, distinguishing one color from another.

While brightness relates to how light or dark a color appears and saturation refers to the intensity or purity of a color, these aspects do not define the color itself. Intensity might refer to the strength or power of the color's appearance but does not help in identifying what the color is. In terms of color theory and perception, hue is the characteristic most closely associated with the identity of a color, making it the primary focus when discussing color differentiation.