What is at the end of a rainbow?

 This question I came across when I was listening to Web radio.

The RJ asked this question to listeners, what is at the end of the rainbow?

I thought it is a complete scientific question. 

We all see rainbow as a semicircle. Rainbow consists of 7 colours. 

We all know that it comes in the order of VIBGYOR, where

V = violet

I = indigo

B = blue

G = green

Y = yellow

O = orange

R = red

These are the 7 colours in a rainbow according to  their wavelength. 

Now coming back to the question, what is at the end of the rainbow?

Rainbow is always seen in semi circle shape. 

Semicircle has 2 ends. Right and left. 

I was confused by thinking that from which side we must tell what is at the end. 

I was sure either it is violet colour or red colour. 

Without giving stress to my mind, I was waiting for RJ to tell the correct answer. 

Soon, the answer is out. 

It is the letter ' w '.

Rainbow = R a I n b o w.

W is at the end of the rainbow !!!!