A tertiary colour is one produced by mixing one primary colour with one secondary colour, in a given colour space. Unlike primary and secondary colours, these are not represented by one firmly established name each, but the following examples include some of the most popular. The term ‘tertiary colour’ was originally coined to refer to ‘neutral’ colours; those made by mixing all three primary colours in a colour space. Examples of these would be white or grey, in the (light) additive system, and brown, grey, or black in the (pigment or paint) subtractive system. This is still the common meaning in most technical literature. Many professionals today prefer the term ‘intermediate colour’ to prevent confusion.