title: xmlhttp.responseText not outputting to innerHTML
body: <p>I'm trying to familiarize myself with Ajax as I will need to use it continually for work.  I'm working through the W3Schools tutorial trying things with my Apache2 server.  I have a file called ajax_info.txt on the server (under /var/www (ubuntu)).  I'm making a call to it and with Firebug I see I get a good response (4 &amp; 200) but it isn't outputting the contents of the file to the DOM.  Here's the code:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
      &lt;head&gt;
          &lt;script&gt;
          var xmlhttp;
          var url = "http://192.168.0.5/ajax_info.txt";
  
          function loadXMLDoc(url, cfunc) {
              if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari
                  xmlhttp = new XMLHttpRequest();
              } else { // code for IE6, IE5
                  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
              }
              xmlhttp.onreadystatechange = cfunc;
              xmlhttp.open("GET", url, true);
              xmlhttp.send();
          }
          function myFunction() {
              loadXMLDoc(url, function () {
                  if (xmlhttp.readyState == 4 &amp;&amp; xmlhttp.status == 200) {
                      document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
                  }
              });
          }
          &lt;/script&gt;
      &lt;/head&gt;
      &lt;body&gt;
          &lt;div id="myDiv"&gt;
              &lt;h2&gt;Let AJAX change this text&lt;/h2&gt;
          &lt;/div&gt;
          &lt;button type="button" onclick="myFunction()"&gt;Change Content&lt;/button&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>I'm not exactly sure what it is I'm doing wrong.  The w3schools tutorial isn't exhaustive by any stretch.  I plan on buying a book, but I'd love to learn these simple GET calls as it will get me headed in the proper direction.  Any suggestions would be greatly appreciated.  </p>