function ajaxFunction() {
  var xmlHttp;
  try {
    // Firefox, Opera 8.0+, Safari
    xmlHttp=new XMLHttpRequest();
    }
  catch (e) {
    // Internet Explorer
    try {
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
    catch (e) {
      try {
        xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
      catch (e) {
        alert("Your browser does not support AJAX!");
        return false;
        }
      }
    }
	return xmlHttp;
}