There are two basic ways colors can be mixed to make other colors. One is by combining color light.

Mixing color light is called additive color mixing, because the combined colors are formed by the adding of light from two or more light sources together. Two or more lights added together will give more illumination than any of the lights by themselves.

If colored light is mixed together, the brightness of the colored lights are added together. This can be seen where the color illumination overlaps. The yellow mixed from red plus green will be brighter than either the red light or green light alone.

White light is formed where all three additive primary colors overlap. Since the white mixture results from the adding of all three color light sources, the white light mixture appears even brighter yet.

By varying the amount of the individual light sources, a full range of colors can be obtained. Television screens and PC monitors use the additive color process.