This happens when you look at an apple and see it is red, this means that all the other colors in the apple are absorbed, except for the red color, permitting only the red color to reflect back to the viewer. All people see color when certain wavelengths of light get absorbed by certain objects, and other colors are reflected or refracted back to your eye. Therefore, starting with red, which has the lowest frequency, then passing through all the colors of the rainbow, each frequency increases until you get to violet, which has the highest frequency. White light, in its purity, consists of all of the visible colors, and since light can perform or behave as a wave, so each color has its very own wave frequency.

Visible light is only a minor part of the radiation spectrum that we as humans can see. Our whole cosmos abounds in electromagnetic radiation, which includes microwaves, radio waves, ultraviolet light, gamma-rays, X-rays, and visible light. Color is energy that is evident all around us, all the time.