I think this illustrates the concept of Big-O complexity pretty good.
O(1): random access to an element in a collection, dependent on indexing— @DynamicWebPaige (@DynamicWebPaige) April 4, 2018
O(n): list iterations
O(n^2): nested loops on the same collection
O(log n): divide and conquer
O(n log n): iterations that use divide and conquer
O(n!): adding a nested loop for every input you have pic.twitter.com/ZiLNxupbaQ