Backbone library has different components, each one with its own intentions and responsibilities, that's why you have to test them differently. Keep it in mind that you should only test your code and not the Backbone built-in functionalities.

In the next sections, you will see what are the parts of your Backbone applications and how to test them; we will start from simple things and then go for more complex ones. Then, you will learn how to isolate modules to only test one module at time.