Get browser details using navigator.
function NavigatorExample() {
  var txt;
  txt = "Browser CodeName: " + navigator.appCodeName;
  txt+= "Browser Name: " + navigator.appName;
  txt+= "Browser Version: " + navigator.appVersion ;
  txt+= "Cookies Enabled: " + navigator.cookieEnabled;
  txt+= "Platform: " + navigator.platform;
  txt+= "User-agent header: " + navigator.userAgent;
}