Big O notation: Calculate time complexity
Time complexity: Common unit: O(1), O(n), O(logN), O(NlogN), O(N^2), O(2^N)
Big O: maximum possible computation time of a program When a program have time complexity O(N), we know it could not be run slower then O(N)
Big Omega: minimum possible computation time of a program When a program have time complexity Omega(N), we know it could not be run faster then Omega(N)