# Big O notation

Big O Notation is a way of saying how much time it takes for a mathematical algorithm to run or how much memory it uses.

The Big O Notation is often used in the context of complexity class.

## Use

Big O Notation is difficult to think about because when you are given a Big O Notation like $O(n^2)$, there is nothing to actually "solve". It is an expression that is meant to give a person a feel for the worst case scenario without them having to do any calculations around it.