AngularJS is a structural framework for dynamic web apps. It lets you use HTML as your template language and lets you extend HTML's syntax to express your application's components clearly and succinctly. Angular's data binding and dependency injection eliminate much of the code you currently have to write. And it all happens within the browser, making it an ideal partner with any server technology.
A few years back developers started using AJAX, and there was a need for complete decoupling between client & server to turn HTML into apps. With Angular.JS, which is a JavaScript framework from Google it is easy to build enterprise-ready single page web apps. A business that needs interactive websites and apps, a rich JavaScript MVC framework like Angular.JS is the best choice.
AngularJS is a powerful JavaScript based development framework to create RICH Internet Application(RIA).It also provides developers options to write client side application (using JavaScript) in a clean MVC(Model View Controller) way. Application written in AngularJS is cross-browser compliant. AngularJS automatically handles JavaScript code suitable for each browser. AngularJS is open source, completely free, and used by thousands of developers around the world.