title: what is the meaning of use two bracket in javascript array
body: <p>I want to change the date format in javaScript and I find this code of "Mike Christensen" that is very nice.
  But my question is about what is meaning of use two bracket in javascript array code at <strong><em>var month line 3</em></strong>.</p>
  
  <pre><code>var mydate = new Date(form.startDate.value);
  var month = ["January", "February", "March", "April", "May", "June",
  "July", "August", "September", "October", "November", "December"]    [mydate.getMonth()];
  var str = month + ' ' + mydate.getFullYear();
  </code></pre>