CHAPTER 12 The Backbone Library Backbone is an excellent library for building JavaScript applications. Its beauty is in its simplicity; the library is very lightweight, giving you a great deal of flexibility while covering all the basics. As with the rest of this book, MVC is the name of the game, and that pattern runs right through the core of Backbone. The library gives you models, controllers, and views--the building blocks for your application. How is Backbone different from other frameworks, such as SproutCore or Cappuccino? Well, the main difference is Backbone's lightweight nature. SproutCore and Cappuc- cino provide rich UI widgets and vast core libraries, and they determine the structure of your HTML for you. Both frameworks measure in the hundreds of kilobytes when packed and gzipped, as well as many megabytes of JavaScript, CSS, and images when