Purple is a range of hues of color occurring between red and blue. In additive light combinations it occurs by mixing the primary colors red and blue in varying proportions. It is a secondary color because two colors (blue and red) make up this color. In subtractive pigments it can be equal to the primary color magenta or be formed by mixing magenta with the colors red or blue, or by mixing just the latter two, in which case a color of low saturation will result. Low saturation will also be caused by adding a certain quantity of the third primary color (green for light or yellow for pigment).

In color theory, a "purple" is defined as any non-spectral color between violet and red (excluding violet and red themselves). The spectral colors violet and indigo are not purples according to color theory but they are purples according to common English usage since they are between red and blue.

In art, purple is the color on the color wheel between magenta and violet and its tints and shades. This color, electric purple, is shown below.

In human color psychology, purple is also associated with royalty and nobility (stemming from classical antiquity when Tyrian purple was only affordable to the elites).