Color triangle Color triangle A colour triangle is an arrangement of colours within a triangle, based on the additive combination of three primary colors at its corners. An additive colour space defined by three primary colors has a chromaticity gamut that is a color triangle, when the amounts of the primaries are constrained to be nonnegative. Before the theory of additive color was proposed by Thomas Young and further developed by James Clerk Maxwell and Hermann von Helmholtz, triangles were also used to organize colors, for example around a system of red, yellow, and blue primary colors. After the development of the
Logo of the BBC programmes and clips from the BBC archives were being sold to be aired on other networks and channels. It was in the early 1960s that the 'bat's wings' logo ceased to be used. It was superseded by the BBC TV logo within a circle, behind which would appear a map of Britain split into broadcast regions. This set the style for a succession of circular images. On 30 September 1963, the BBC's globe logo first appeared. This was a striped line broken in the middle by a globe, with BBC1 in block letters below it. When it appeared, the continuity