Primary color In
traditional color theory, it is believed that all colors can be mixed from three universal primary - or pure - colors, which were originally believed to be red, yellow and blue pigments (representing the
RYB color model). However, modern
color science does not recognize universal primary colors and only defines primary colors for a given
color model or
color space.
RGB and
CMYK color models are popular color models in modern color science, but are only chosen as efficient primaries, in that their combination leads to a large gamut. However, any three primaries can produce a viable color gamut. The RYB model continues to be used and taught as a color model for practical
color mixing in the
visual arts.
Secondary color A secondary color is an even mixture of two primary colors. For a given
color model, secondary colors have no special meaning, but are useful when comparing additive and subtractive color models.
Intermediate color An intermediate color is any mixture of a secondary and a primary color. They are often visualized as
even mixtures, but intermediate colors can arise from any mixture proportion. Therefore any color that is not a secondary or primary color is an intermediate color.
Tertiary color Tertiary color has two common, conflicting definitions, depending on context. In traditional
color theory, which applies mostly to practical painting, a tertiary color is an
even mixture between two secondary colors, i.e. a mixture of three primaries in 1:2:1 proportion. This definition is used by color theorists, such as Moses Harris and Josef Albers. The result is approximately a less saturated form of the dominant primary color of the mixture. Under this definition, a color model has 3 tertiary colors. More recently, an alternative definition has emerged that is more applicable to digital media, where a tertiary color is an intermediate color resulting from an
even mixture of a primary and a secondary color, i.e. a mixture of the primaries in 3:1:0 proportion. The result yields a maximum saturation for a given hue. Under this definition, a color model has 6 tertiary colors.
Quaternary color A quaternary color is a seldom-used descriptor that is the conceptual extension of a tertiary color. Quaternary colors have no special use or status in color theory or color science. Under the traditional definition, a quaternary color is the even mixture of two tertiary colors, as demonstrated by
Charles Hayter. These quaternary colors have contributions from all three primaries in 3-3-2 proportions, so are very desaturated (even mixtures of three primaries gives a neutral color: zero saturation). Under this definition, a color model has 3 quaternary colors. Under the modern definition, a quaternary color is the even mixture of a tertiary color with either a secondary or primary color. Quaternary colors are sometimes given a maximum saturation for their hue. Under this definition, a color model has 12 quaternary colors. ==RGB and CMYK==