var browserName=navigator.appName;
var browserVersion=parseInt(navigator.appVersion);
var browser;

if (browserName == "Netscape" && browserVersion >= 5) {
browser="nn6";
}
else if (browserName == "Netscape" && browserVersion == 4) {
browser="nn4";
}
else if (browserName == "Microsoft Internet Explorer" && browserVersion == 4 && navigator.appVersion.indexOf("MSIE6.0") != -1 ) {
browser="ie6";
}
else if (browserName == "Microsoft Internet Explorer" && browserVersion == 4 && navigator.appVersion.indexOf("MSIE5.5") != -1 ) {
browser="ie55";
}
else if (browserName == "Microsoft Internet Explorer" && browserVersion == 4 && navigator.appVersion.indexOf("MSIE5.0") != -1 ) {
browser="ie5";
}
else if (browserName == "Microsoft Internet Explorer" && browserVersion == 4 ) {
browser="ie4";
}



//Handle Browser Specific Code
if (browser=="nn6" || browser=="ie6" || browser=="ie55" || browser=="ie5") {
//specific code here
}
else if (browser=="nn4") {
//specific javascript code for nn4 goes here

}
else if (browser=="ie4") {
//specific javascript code for ie4 goes here
}