AI Recommendation Engines are powerful and common uses of AI. They are able to learn from all customer data and work out accurately what products particular customers may be interested in based on the behaviour and demographic of other customers. How a real AI Recommendation Engine/ Recommendation System (Recsys) works is different to how you might think - if you're used to traditional software techniques. It uses some sophisticated maths that are actually interesting, using three dimensional mappings as opposed to tonnes of database calls and bog standard code. Here I discuss how it all works.