ROYGBIV

ROYGBIV or Roy G. Biv is an acronym for the sequence of hues commonly described as making up a rainbow: red, orange, yellow, green, blue, indigo and violet.

A rainbow spans a continuous spectrum of colors; the distinct bands are an artifact of human color vision. In ROYGBIV, the colors are arranged in the order of decreasing wavelengths, with red being 650 nm and violet being about 400 nm. The acronym is memorable because Roy is a common male given name, so Roy G. Biv sounds like a first name, middle initial, and a last name.

In Classical Antiquity, Aristotle claimed there was a fundamental scale of seven basic colors. In the Renaissance, several artists tried to establish a new sequence of up to seven primary colors from which all other colors could be mixed. In line with this artistic tradition, Newton divided his color circle, which he constructed to explain additive color mixing, into seven colors. His color sequence including the tertiary color indigo is kept alive today by the Roy G. Biv mnemonic. Originally he used only five colors, but later he added orange and indigo to match the number of musical notes in the major scale.

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