Green is a colour between the yellow and blue colours in the rainbow. Green is a primary colour (a colour that can be mixed with another color) of light. The others are red and blue.
Green and blue are next to each other on the spectrum, and there are languages which do not distinguish between them. Examples are old Chinese, Thai, old Japanese, and Vietnamese.
Green paint can be made by mixing yellow paint and blue tempera paint together.
Green light, like all light, is quanta—composed of photons. The wavelength of green light is about 550 nanometers (one-billionth of a meter).
Most leaves of growing plants, such as trees and bushes, are green. This is because there is a chemical in leaves, called chlorophyll, which is coloured green.