Ajax Engine _ajax

function Ajaxfunction () {
    var xmlHttp;
    try {//Firefox, Opera 8.0+, Safari
	xmlHttp = new XMLHttpRequest ();
    } 
    catch (E) {
	try {//Internet Explorer
	    xmlHttp = new ActiveXObject ("Msxml2.xmlhttp");
	} 
	catch (E) {
	    try {
		xmlHttp = new ActiveXObject ("Microsoft.XMLHTTP");
	    } 
	    catch (e) {}}} return
    xmlHttp