A polyglot data model is a common physical data model that can generate schemas for different technologies while remaining technology agnostic. It allows for denormalization and complex data types. The polyglot model acts as a master model that physical target models can be derived from. Changes are made at the polyglot level and then target models are refreshed. The document discusses how to create, promote, and derive target models from a polyglot data model as well as handling changes between the models.