Google’s AlphaGo is an extraordinary breakthrough for Artificial Intelligence. The game of 19×19 Go has 1.74×10^172 unique positions and is about a ‘googol’ times harder to calculate than chess. Experts thought it would take at least another decade before AI would be able to beat the best human players. So how did Google tackle this problem? What algorithms did they use and how do they work? In this session we’ll describe how game AI works, from a very simple game, to tic tac toe, to chess and finally to Go. It explains the algorithms used for solving each of those games. The talk ends with how all these traditional algorithms fail with the game of Go and how AlphaGo managed to beat the best human players in the world.