Question

A note added at the end of a letter
What is word for substitution

Answer 1

Answer:

The word which you are looking for is PS in this case. The word PS stands for Postscript.

This is basically a note added at the end of any letter because it is used to indicate an important message which got missed out in the actual letter.

Explanation:

This after thought comes to the person writing the letter when they have written the letter and are practically at the end. When this happens they realize that they missed out on something important so they mention it in this manner.

For example,

XXXXXXXX

XXXXXXX

XXXXXXXx

P.S Don't forget to feed the dog.