title: difference between getLoginStatus and getUser
body: <p>Consider the following code snippet from developrs.facebook.com</p>
  
  <pre><code>FB.getLoginStatus(function(response) {
    if (response.status === 'connected') {
      // the user is logged in and has authenticated your
      // app, and response.authResponse supplies
      // the user's ID, a valid access token, a signed
      // request, and the time the access token 
      // and signed request each expire
      var uid = response.authResponse.userID;
      var accessToken = response.authResponse.accessToken;
    } else if (response.status === 'not_authorized') {
      // the user is logged in to Facebook, 
      // but has not authenticated your app
    } else {
      // the user isn't logged in to Facebook.
    }
   });
  </code></pre>
  
  <p>Next,
  consider the following</p>
  
  <pre><code>$facebook = new Facebook($config);              
  
  $user = $facebook-&gt;getUser();
  $userdata = null;
  if($user)
  {
      try{
          $userdata = $facebook-&gt;api('/me');
      }catch(FacebookApiException $e){
          $e-&gt;getMessage();
      }
  }
  
  $loginUrl   = $facebook-&gt;getLoginUrl(array('scope' =&gt; $scope);
  if(!$userdata)
  {                   
      //redirect to login
  }
  </code></pre>
  
  <p>My second code is doing everything that the first code promises to do . So why should i use the first method?</p>