detect any IE Browser. checks for ActiveXObject which is exclusively available on IE. Works for IE5 -11. Use only when feature detection won't give desired results.

detect-IE.js

//place script in head and after modernizr.
(function(){
  var html = document.getElementsByTagName('HTML')[0];
  
  if("ActiveXObject" in window){
    html.className += ' is-IE';
  }
})()

getInternetExplorerVersion.js

	function getInternetExplorerVersion()
	{
	  var rv = -1;
	  if (navigator.appName == 'Microsoft Internet Explorer')
	  {
	    var ua = navigator.userAgent;
	    var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
	    if (re.exec(ua) != null)
	      rv = parseFloat( RegExp.$1 );
	  }
	  else if (navigator.appName == 'Netscape')
	  {
	    var ua = navigator.userAgent;
	    var re  = new RegExp("Trident/.*rv:([0-9]{1,}[\.0-9]{0,})");
	    if (re.exec(ua) != null)
	      rv = parseFloat( RegExp.$1 );
	  }
	  return rv;
	}