This document discusses how machine learning algorithms can be used to optimize websites through data-driven experimentation and personalization. It describes techniques like multi-armed bandits, Bayesian modeling, and Thompson sampling that can be used to test multiple variants and identify high performing content. Behavioral targeting and personalization approaches are also discussed that use visitor data to tailor website experiences. While machine learning shows promise in analyzing customer journeys, the document notes that fully replacing human judgment may still be premature given the complexity involved.