title: AngularJS : Difference between the $observe and $watch methods
body: <p>I know that both <code>Watchers</code> and <code>Observers</code> are computed as soon as something in <code>$scope</code> changes in AngularJS. But couldn't understand what exactly is the difference between the two.</p>
  
  <p>My initial understanding is that <code>Observers</code> are computed for angular expressions which are conditions on the HTML side where as <code>Watchers</code> executed when <code>$scope.$watch()</code> function is executed. Am I thinking properly?</p>