How is Amazon Able to Recommend Other Things to Buy? How Does the Recommendation Engine Work?

Amazon's recommender system works by analyzing past customer behavior and then using machine learning algorithms to build models of what types of products different customers are likely to want.

For example, if a customer has previously bought a lot of books about history, Amazon's recommender system will suggest other historical books that the customer might be interested in. And if a customer has never bought anything from Amazon before, the system will recommend products that other people with similar interests have purchased.