var M2   = (navigator.userAgent.indexOf("Mozilla/2") != -1);
var M3   = (navigator.userAgent.indexOf("Mozilla/3") != -1);
var M4   = (navigator.userAgent.indexOf("Mozilla/4") != -1);
var M5   = (navigator.userAgent.indexOf("Mozilla/5") != -1);

var OP   = (navigator.userAgent.indexOf("Opera") != -1);
var OP3  = (navigator.userAgent.indexOf("Opera/3") != -1) && M3;
var OP35 = (navigator.userAgent.indexOf("Opera/3") != -1) && M4;
var OP36 = (navigator.userAgent.indexOf("Opera 3") != -1) && M4;
var OP4  = (navigator.userAgent.indexOf("Opera 4") != -1) || (navigator.userAgent.indexOf("Opera/4") != -1);
var OP5  = (navigator.userAgent.indexOf("Opera 5") != -1) || (navigator.userAgent.indexOf("Opera/5") != -1);
var OP6  = (navigator.userAgent.indexOf("Opera 6") != -1) || (navigator.userAgent.indexOf("Opera/6") != -1);

var IE   = (navigator.userAgent.indexOf("MSIE") != -1) && !OP;
var IE3  = (navigator.userAgent.indexOf("MSIE 3") != -1);
var IE4  = (navigator.userAgent.indexOf("MSIE 4") != -1);
var IE50 = (navigator.userAgent.indexOf("MSIE 5.0") != -1) && !OP;
var IE55 = (navigator.userAgent.indexOf("MSIE 5.5") != -1) && !OP;
var IE60 = (navigator.userAgent.indexOf("MSIE 6.0") != -1) && !OP;

var NN   = (navigator.appName == "Netscape") && !OP;
var NN2  = (navigator.appName == "Netscape") && M2 && !OP;
var NN3  = (navigator.appName == "Netscape") && M3 && !OP;
var NN4  = (navigator.appName == "Netscape") && M4 && !OP;
var NN6  = (navigator.userAgent.indexOf("Netscape6") != -1) && M5 && !OP;
var NN7  = (navigator.userAgent.indexOf("Netscape/7") != -1) && M5 && !OP;

var MOZ1 = M5 && (navigator.userAgent.indexOf("Netscape") == -1) && !OP && (navigator.userAgent.indexOf("Gecko") != -1) && (navigator.userAgent.indexOf("rv:1") != -1);