Javascript Essentials Part 2

<META HTTP-EQUIV="REFRESH" CONTENT="300">

<script language="JavaScript">
document.write('<form><input type=button value="Refresh the browser with button" onClick="history.go()"></form>')
</script>

<script language="JavaScript">
//configure refresh interval (in seconds)
var countDownInterval=60;
//configure width of displayed text, in px (applicable only in NS4)
var c_reloadwidth=200
</script> 
<ilayer id="c_reload" width=&{c_reloadwidth}; ><layer id="c_reload2" width=&{c_reloadwidth}; left=0 top=0></layer></ilayer>
<script>
var countDownTime=countDownInterval+1;
function countDown(){
countDownTime--;
if (countDownTime <=0){
countDownTime=countDownInterval;
clearTimeout(counter)
window.location.reload()
return
}
if (document.all) //if IE 4+
document.all.countDownText.innerText = countDownTime+" ";
else if (document.getElementById) //else if NS6+
document.getElementById("countDownText").innerHTML=countDownTime+" "
else if (document.layers){ //CHANGE TEXT BELOW TO YOUR OWN
document.c_reload.document.c_reload2.document.write('Next <a href="javascript:window.location.reload()">refresh</a> in <b id="countDownText">'+countDownTime+' </b> seconds')
document.c_reload.document.c_reload2.document.close()
}
counter=setTimeout("countDown()", 1000);
}
function startit(){
if (document.all||document.getElementById) //CHANGE TEXT BELOW TO YOUR OWN
document.write('Next <a href="javascript:window.location.reload()">refresh</a> in <b id="countDownText">'+countDownTime+' </b> seconds')
countDown()
}
if (document.all||document.getElementById)
startit()
else
window.onload=startit
</script>