var agent=navigator.userAgent.toLowerCase();

var major_v = parseInt(navigator.appVersion);
if (isNaN(major_v)){major_v=0;}

var appName = navigator.appName;

var is_netscape = (appName.indexOf('Netscape')!=-1);
var is_explorer = ( (agent.indexOf('msie')!=-1)&&(agent.indexOf('opera')==-1) );

var is_win= (agent.indexOf('win')!=-1);

var is_gecko = (agent.indexOf('gecko') != -1);

if(agent.indexOf("msie 3")!=-1){
major_v=3;
}
else if(agent.indexOf("msie 4")!=-1){
major_v=4;
}
else if(agent.indexOf("msie 5")!=-1){
major_v=5;
}
else if(agent.indexOf("msie 6")!=-1){
major_v=6;
}
else if(agent.indexOf("msie 7")!=-1){
major_v=7;
}
var is_aol   = (agent.indexOf("aol") != -1);
var is_opera = (agent.indexOf("opera") != -1);
var is_opera2 = (agent.indexOf("opera 2") != -1 || agent.indexOf("opera/2") != -1);
var is_opera3 = (agent.indexOf("opera 3") != -1 || agent.indexOf("opera/3") != -1);
var is_opera4 = (agent.indexOf("opera 4") != -1 || agent.indexOf("opera/4") != -1);
var is_opera5 = (agent.indexOf("opera 5") != -1 || agent.indexOf("opera/5") != -1);
var is_opera6 = (agent.indexOf("opera 6") != -1 || agent.indexOf("opera/6") != -1);
var is_opera7 = (agent.indexOf("opera 7") != -1 || agent.indexOf("opera/7") != -1);
var is_opera5up = (is_opera && !is_opera2 && !is_opera3 && !is_opera4);
var is_opera6up = (is_opera && !is_opera2 && !is_opera3 && !is_opera4 && !is_opera5);
var is_opera7up  = (is_opera && !is_opera2 && !is_opera3 && !is_opera4 && !is_opera5 && !is_opera6);
//korrigerad 2002-05-06 mö
//var is_explorer4 = (is_explorer && (agent.indexOf("msie 5")==-1));
var is_explorer4 = (is_explorer && (major_v==4));
var is_explorer4up = (is_explorer && (major_v>=4));
var is_explorer5up =(is_explorer && (agent.indexOf("msie 4")==-1) && !major_v<4 );
var is_netscape4 = (is_netscape && (major_v==4));
var is_netscape4up = (is_netscape && (major_v>=4));
var is_netscape6up =(is_netscape && (major_v>4));


var is_mac    = (agent.indexOf("mac")!=-1);


//alert("is_opera7up: "+is_opera7up+"   is_explorer4: "+is_explorer4+"  is_explorer4up: "+is_explorer4up+ "   is_netscape6up: "+is_netscape6up);

//alert("appName: "+appName + "major_v: "+major_v+"  navigator.appVersion:"+navigator.appVersion);