Knockout JavaScript or simply kojs, helps you creating dynamic JavaScript UIs using the Model-View-ViewModel (MVVM) pattern.
Don’t ignore this, because it will be a part of ASP.NET MVC4. 
If you don’t know knockoutjs, you can start the interactive tutorials via http://learn.knockoutjs.com/.
<p>Teusje is: <span data-bind="text: someCoolText" /></p> <p>Insert some cool text: <input data-bind:"value: someCoolText" /></p>
var viewModel = {
someCoolText: ko.observable("Funky")
};
ko.applyBindings(viewModel);
Have fun! 
