AngularJS is an open source web application framework mainly maintained by Google and by a community of individuals and corporations to address many of the challenges encountered in developing single-page applications. It aims to simplify both the development and the testing of such applications by providing a framework for client-side model–view–controller (MVC) and model–view–view-model (MVVM) architectures, along with components commonly used in rich Internet applications.
Single Page Applications
AngularJS helps you build single page applications like Gmail. These applications are fast and sleek like desktop apps. You do not have to wait for page reloads.
Real time Applications
AngularJS makes it easy for you to build realtime applications as it has two-way data binding. You can program it to update the webpage **without a page reload** as and when the data changes on the backend and is sent to the frontend.
Angular JS makes it incredibly easy to build applications which scale beautifully, both from a development point of view as well as from a utilization point of view.