The document discusses personalizing the user experience. It defines personalization as a tactic for optimization that involves a 4-step process: 1) visitors engage with a touchpoint, 2) data about the visitor is collected, 3) the visitor is profiled using the data, 4) the touchpoint is personalized for the next interaction. It provides examples of how to start personalizing, such as changing what appears on a homepage or in an email for a target profile, and emphasizes testing changes using an optimization approach.