// Create the request object
  var xml = new XMLHttpRequest();
  
  // Open the asynchronous POST request
  xml.open("GET", "/some/url.cgi", true);
  
  // Watch for when the state of the document gets updated
  xml.onreadystatechange = function(){
      // Wait until the data is fully loaded
      if ( xml.readyState == 4 ) {
  
          // xml.responseXML contains the XML Document (if one was returned)
          // xml.responseText contains the response text (if no XML document was provided)
  
          // Clean up after ourselves, to avoid memory leaks
          xml = null;
      }
  };
  
  // Establish the connection to the server
  xml.send();