In traditional colour theory (subtractive colour mixing, used in painting and art), the three primary colours are red, yellow, and blue. These are called primary because they cannot be created by mixing other colours together, and all other colours in the spectrum can be produced by combining them in various proportions.
Red, white, and black are not all primaries; white and black are neutral values used to create tints and shades, not to mix new hues. Orange, green, and violet are the three secondary colours, each made by mixing two primaries. Red, green, and blue (RGB) are the primary colours of additive colour mixing (light, as used in screens and digital displays), not the primary colours of traditional art and painting.
Exam tip: distinguish between subtractive primaries (red, yellow, blue - used in painting) and additive primaries (red, green, blue - used in light and screens).
