The Backbone.Model class is a container for data in the first place. Additionally you can write functions that work on the individual records.
To oversimplify the View class, it can be used to bring data to the screen.
This tutorial is an easy to follow example, how to use the library Backbone.js for creating dynamic views.
The class Backbone.Collection is used to organize the elements in a list.
Backbone helps your application to react on data changes. There are ways to listen to attribute changes (e. g. a task gets completed) or object creation and destruction.