Understanding Modules

AngularJS modules are containers that allow you to compartmentalize and organize your code into concise, clean, reusable chunks. Modules themselves do not provide direct functionality, but they contain instances of other objects, such as controllers, filters, services, animations, etc. that do.

You build a module by defining the objects it provides. Then, by linking together modules through dependency injection, you build a full application.

AngularJS is built on the module principle. Most of the functionality provided by AngularJS is built into a module named ng, which contains most of the directives and services used throughout this book.