In Part 1 of this series I discussed the basics of data binding in KnockoutJS. In this post, I’ll dive a little deeper in the the binding behaviors of KnockoutJS and show how you can build really responsive web apps using client side development techniques.

While data binding is an important part of KnockoutJS development, it is only part of what makes KnockoutJS so attractive. KnockoutJS is a JavaScript based implementation of the MVVM design pattern which is a derivation of the Presentation Model as described by Martin Fowler. Martin Fowler sums up the Presentation Model like this:

The essence of a Presentation Model is of a fully self-contained class that represents all the data and behavior of the UI window, but without any of the controls used to render that UI on the screen. A view then simply projects the state of the presentation model onto the glass.

As Fowler explains, the Presentation Model class should represent both the data and the behavior which are then bound to the view. Let’s dive into how KnockoutJS handles binding behaviors to your HTML.