Angular UI Router is a routing framework for angular js.
Angular JS already provides ngRoute module for routing. It is a basic routing lib where we can specify just one view and controller for any route. We can’t achieve nested view through ngRoute. So that we are using UI Router.
To get Started
lets include the library after we include Angular in our intex.html
UI Router package is distributed using npm, the node package manager.
npm install --save angular-ui-router
Add a Dependency to UI Router
... read the whole story at esakkimuthu.me.