Comparatives and superlatives are used to compare people, animals, things, etc., with each other.
When you compare things, you look at more than one thing and see if they are the same or different.
1 That elephant is big, but the other one is bigger.
The elephant over there is the biggest!
2 My brother is rich, but my father is richer.
My grandfather is the richest of them all!
Bigger and richer are comparatives. Biggest and richest are superlatives