@ngdoc overview @name Developer Guide: Initializing Angular: Automatic Initialization @description For Angular to manage the DOM for your application, it needs to compile some or all of an HTML page. Angular does this initialization automatically when you load the angular.js script into your page and insert an `ng-app` directive (attribute) into one of the page's elements. For example, we can tell Angular to initialize the entire document:



  
    
  
  
    I can add: {{ 1+2 }}.

You can also tell Angular to manage only a portion of a page. You would want to do this if you are using some other framework to manage other parts of the page. You do this by placing the `ng-app` directive on one or more container elements in the document. For example:


  I can add: {{ 1+2 }}

You can also ask `ng-app` to load additional {@link api/angular.module modules} containing services, directives or filers that you'll use on the page.

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