title: "var d = document;" Is it really useful?
body: <p>I regularly see JavaScript code with variables like this:</p>
  
  <pre><code>var w = window,
      d = document,
      e = d.documentElement,
      g = d.body;
  
  w.addEventListener('resize', function () {
      ...
      d.querySelectorAll(...);
      ...
  });
  </code></pre>
  
  <p>I just wonder if there is an interest in using these kinds of variables? (Other than decreasing the amount of code if there are many calls to "document" or "window")
  I think the answer is no, but just in case ...</p>