Without color. Achromatic grays, like black and white, have no hue and no saturation: only value.
Color scheme made up of 3-4 hues that lie adjacent to one another on the spectrum / color circle.
Occurs when color fragments are fused by the eye to appear as seamless tonal transitions.
Color observed as projected light. The additive color primaries are red, green, and blue. When combined in equal amounts, the result is pure, white light.
The traditional subtractive color system is used by traditional pigments and dyes. The traditional subtractive primaries are red, yellow and blue. In theory, when mixed in equal amounts, they create pure black. In reality they gradually progress to darker and darker hues - never quite reaching pure black.
Visual effect created when a warm hue, like red or yellow, is paired with a cool hue, like green or blue.