Facade
The use of facade as a term to refer to a design pattern comes directly from building architecture. That is, a facade is the face of a building that is normally made to look more appealing than the rest of it. In programming, facades can help to hide the ugly details of an implementation.
The Facade design pattern itself aims to provide a nicer, simpler way to work with a family of classes or interfaces. We previously discussed the idea of a family of classes when covering the Abstract Factory design pattern. The Abstract Factory design pattern focuses on creating related classes, while the Facade design pattern focuses on working with them once they have been created.
To better understand this, let's go back to the example we used for the Abstract Factory design pattern. In order to be able to start our server from a configuration using our Abstract Factory, we could provide users of our library with a set of instructions:
