An algorithm must be seen to be believed.
Donald Knuth
In the first six chapters, you learned about the ecosystem and infrastructure around recommender systems. Now, in part 2, we’ll look at the recommender system algorithms. We’ll look at how to use the data that a system can collect to calculate what things it can recommend to a user. We’ll also discuss how you can evaluate a recommender system and look at the strengths and weaknesses of each algorithm.