title: why the controller function isn't executing Angular Js 1.5.5
body: <p>I'm quite new to Angular js (4 hours of experiance) so I'll be straightforward :<br>
  i'm coding the basic examples of an online course, it was recorded in 2014.<br>
  The thing is that the function inside the controller is not executing, i know that i'm missing some very basic thing, but i searched for related questions here on StackOverflow and it didn't help, so I'm reling on.<br>
  here is the code snippets:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;!-- the index.html file --&gt;
  &lt;html ng-app="myApp"&gt;
  &lt;head&gt;
      &lt;title&gt;Angular Udemy chap 2&lt;/title&gt;
      &lt;script src="angular.min.js"&gt;&lt;/script&gt;
      &lt;script src="app.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div   ng-controlller="mainController"&gt;  
          &lt;h1&gt; Hello {{ name }} !!! &lt;/h1&gt;
      &lt;/div&gt; 
  &lt;/body&gt; 
  </code></pre>
  
  <p>  </p>
  
  <pre><code>/* the app.js file */
  var myApp = angular.module('myApp',[]);
  myApp.controller('mainController',["$scope",function($scope){
  $scope.name = "ElBarto";
  
  }]);
  </code></pre>