UserAgent = navigator.userAgent.toLowerCase(); 
	var isGecko = (!document.all && !window.opera && document.getElementById) ? true : false;
	var isOpera = (window.opera) ? true : false;
	var isIE = (document.all && !window.opera) ? true : false;
	var isIE6 = (isIE && document.createAttribute && !window.XMLHttpRequest) ? true : false;
	var isIE7 = (isIE && window.XMLHttpRequest) ? true : false; 
	var isSafari = (UserAgent.indexOf("safari") !== -1) ? true : false;
	var isChrome = (UserAgent.indexOf('chrome') !== -1) ? true : false;
	//gitHub version: https://gist.github.com/527683
	var ie = (function() {

	    var v = 3, div = document.createElement('div'), a = div.all || [];

	    while (div.innerHTML = '<!--[if gt IE '+(++v)+']><br><![endif]-->', a[0]); 

	    return v > 4 ? v : !v;

	}());