function Browser()
{
    var ua, s, i;
    
    this.isIE    = false;
    this.isNS    = false;
    this.isOpera = false;
    this.version = null;

    ua = navigator.userAgent;
    
    s = "MSIE";
    if ((i = ua.indexOf(s)) >= 0)
    {
        this.isIE = true;
        this.version = parseFloat(ua.substr(i + s.length));
        return;
    }
  
    s = "Netscape6/";
    if ((i = ua.indexOf(s)) >= 0)
    {
        this.isNS = true;
        this.version = parseFloat(ua.substr(i + s.length));
        return;
    }

    // Treat any other "Gecko" browser as NS 6.1.
    s = "Gecko";
    if ((i = ua.indexOf(s)) >= 0)
    {
        this.isNS = true;
        this.version = 6.1;
        return;
    }
    
    s = "Opera";
    if ((i = ua.indexOf(s)) >= 0)
    {
        this.isOpera = true;
        this.version = parseFloat(ua.substr(i + s.length + 1));
        return;
    }
}