Backbone.js (with Introduction to Testing) Prototypal Inheritance and Extension

Since JavaScript currently lacks a "class" keyword, subclass are created by extending Backbone core components are essentially the constructors and the instances are objects created by using the "new" keyword. Constructor and initialize behavior can be overridden in every Backbone class. Constructor functionality is the first code to fire when an object is instantiated. Initializing code runs after all constructor code has completed. The event system is baked into all Backbone components. It's a synchronous system where event handlers will be called immediately after an event is triggered.