We began the chapter by first understanding the Structural design patterns. You then learned about the Façade design pattern and the context in which it's used. We understood the basis of Façade and how it is effectively used in software architecture. We looked at how Façade design patterns create a simplified interface for clients to use. They simplify the complexity of subsystems so that the client benefits.

The Façade doesn't encapsulate the subsystem, and the client is free to access the subsystems even without going through the Façade. You also learned the pattern with a UML diagram and sample code implementation in Python v3.5. We understood the principle of least knowledge and how its philosophy governs the Façade design patterns.

We also covered a section on FAQs that would help you get more ideas on the pattern and its possible disadvantages. We're now geared up to learn more Structural patterns in the chapters to come.