What we notice most about light is color. We see colors the way we do because of the way light is reflected or absorbed. The reason something appears red is because all of the colors in white light are absorbed except red. The red light is reflected to our eyes and so we see the color red.
Color comes from the visible spectrum of light.
The colors that make up white light from longest to shortest wavelength are red, orange, yellow, green, blue, indigo and violet. In any system of colors, those that cannot be mixed from any of the others are called primary colors. The primary colors of light are red, green and blue. From these three colors every other color of light can be made. Paint pigments mix differently than light.