Knockout
Tool to create rich, responsive UIs with JavaScript
...Get started with knockout.js quickly, learning to build single-page applications, custom bindings and more with interactive tutorials. Knockout is a JavaScript MVVM (a modern variant of MVC) library that makes it easier to create rich, desktop-like user interfaces with JavaScript and HTML. It uses observers to make your UI automatically stay in sync with an underlying data model, along with a powerful and extensible set of declarative bindings to enable productive development. For Node.js developers, Knockout is also available from npm.