Grey

Grey or gray is an achromatic or neutral color.

Complementary colors are defined to mix to grey, either additively or subtractively, and many color models place complements opposite each other in a color wheel. To produce grey in RGB displays, the R, G, and B primary light sources are combined in proportions equal to that of the white point. In four-color printing, greys are produced either by the black channel, or by an approximately equal combination of CMY primaries. Images which consist wholly of neutral colors are called monochrome, black-and-white or greyscale.

The first recorded use of grey as a color name in the English language was in AD 700. Grey is the British, Canadian, Australian, Irish, New Zealand and South African spelling, although gray remained in common usage in the UK until the second half of the 20th century. Gray is the preferred American spelling, although grey is an accepted variant. Gray became the preferred spelling in American English around 1825.