What is at the end of the rainbow?

The letter W

A rainbow is created when sunlight reflects off water droplets. It is not an actual physical object that one can touch, but rather an optical illusion that is seen only from a certain angle. As a person tries to approach the end of a rainbow, it appears to move farther away. So when we talk about the end of a rainbow it is not a physical end. It is just the last letter of the word rainbow itself.

The colors of the rainbow, in order, are red, orange, yellow, green, blue, indigo and violet.