The colour wheel is said to be one of the best tools for visualising the relationships between colours. It can take many forms, from simple, with just a handful of colours, to more complex versions, where they contain many colours. The colour wheel was originally devised by Sir Isaac Newton, back in 1666. One of the most useful colour wheels and indeed the one that will be discussed here, is the '12 Step Colour Wheel', which contains twelve pure hues that are equidistant to one another and is based on the RYB or Artists Colour Model.
There are a number of concepts that can be used to create a colour scheme, which utilise the colour wheel. These are described in the next section on Colour Harmony.
Primary, Secondary and Tertiary Colours
The colour wheel contains primary, secondary and tertiary colours.
The primary colours are those from the RYB Colour Model, red, yellow and blue. They are named as such because they cannot be produced by combining any other colours. They are also used to produce all other colours.
Secondary colours are those that are produced by combining two of the primary colours. They are orange, green and violet.
Finally, tertiary colours are those that are produced by combining a primary and secondary colour. These are red-orange, orange-yellow, yellow-green, green-blue, blue-violet and violet-red.
Warm and Cool Colours
As well as the colours on the colour wheel being classified as primary, secondary or tertiary, they can also be divided into warm and cool colours. All colours between red-violet and yellow are classed as warm, with those between yellow-green and violet being classed as cool.