//　Macintosh           　->  MacOS
            //　Windows95/98/NT/2000  ->　Windows
            function getOSType()
            {
                var uAgent  = navigator.userAgent.toUpperCase();
                if (uAgent.indexOf("MAC") >= 0) return "MacOS";
                if (uAgent.indexOf("WIN") >= 0) return "Windows";
                if (uAgent.indexOf("X11") >= 0) return "UNIX";
                return "";
            }
            //　Netscape Navigator ->  Netscape
            //　Internet Explorer  ->　Explorer
            function getBrowserName()
            {
                var aName  = navigator.appName.toUpperCase();
                if (aName.indexOf("NETSCAPE") >= 0)  return "Netscape";
                if (aName.indexOf("MICROSOFT") >= 0) return "Explorer";
                return "";
            }
            function getBrowserVersion()
            {
                    var browser = getBrowserName();
                    var version = 0;
                    var s = 0;
                    var e = 0;
                    var appVer  = navigator.appVersion;
                    if (browser == "Netscape")
                    {
                            s = appVer.indexOf(" ",0);
                            version = eval(appVer.substring(0,s));
                            if (version >= 5) version++;
                    }
                    if (browser == "Explorer")
                    {
                            appVer  = navigator.userAgent;
                            s = appVer.indexOf("MSIE ",0) + 5;
                            e = appVer.indexOf(";",s);
                            version = eval(appVer.substring(s,e));
                    }
                    return version;
            }