The document discusses the Lego Data Layer, which provides a standardized structure for collecting analytics data about user interactions on websites. It involves tracking interactions as events with a subject, verb, object, and context. Entities like products, users, and transactions are identified and standardized attributes are collected for each. The data is structured to link interactions to the relevant business entities and allow attributes of those entities to be tracked across interactions. This provides a consistent way to analyze user behavior and attributes in a structured format.