What is your favourite colour? Mine is Yellow! Colour plays an important role in the world. Colour can sway your thinking, change actions and cause reactions. It is a powerful form of communication. Not everyone will react the same way to the same colour. Colours are commonly divided into two categories: warm and cool colours. Warm colours include red, orange, yellow provide the illusion of heat and warmth. Cool colours include blue, purple and green provide a sense of calm a