title: What's the difference between (typeof variable === "function") and jQuery.isFunction()?
body: <p>I have always used <code>(typeof variable === "function")</code> and I stumbled across <code>jQuery.isFunction()</code> and I was wondering:</p>
  
  <ol>
  <li>What is the difference between the typeof method and jQuery's method? And not only what the difference is, but</li>
  <li>When is it appropriate to use the typeof method and when is it appropriate to use jQuery's method?</li>
  </ol>