title: Promise : then vs then + catch
body: <p>Is there any difference between the 2 followings codes ?</p>
  
  <pre><code>myPromise.then(function() {
      console.log('success');
  }).catch(function() {
      console.log('error');
  });
  
  myPromise.then(function() {
      console.log('success');
  }, function() {
      console.log('error');
  });
  </code></pre>
  
  <p>I know <code>then</code> and <code>catch</code> returns new promises resolved or rejected with the value returns in the callback. But i see the 2 codes around the web and i'm curious about the real differences between the 2 codes.</p>