What makes the different colors of a rainbow?

To see all the colors of a rainbow is one of the most beautiful phenomenons in meteorology. 

The normal portrayal of a rainbow is made of seven colors (red, orange, yellow, green, blue, indigo and violet).  The different colors are caused by the way light is refracted through raindrops. 

As sunlight passes between two medians of different density, such as air and a raindrop, the different colors are refracted (or bent) at different angels.  The change of angle causes each individual color to reemerge from the drop, instead of one ray like it entered. 

You may have prisms around the house, or even experimented with them in science class.  The same bending of light occurs in them causing the colors of a rainbow to be seen on the walls.