Who is Roy G. BiV?

He's just about the best dressed fellow in the universe and the letters of his name spell out the colors of his costume. The R is for red, 0 for orange and Y for yellow. The G is for green The B is for blue, the I is for indigo and the V is for violet. This radiant array is the colors of the rainbow.

Roy G. Biv, of course, is not a person. His name is a clever device to help you remember the vivid bands of merging colors which form the spectrum of white light   seen at its glorious best in the rainbow.