You can do it two ways, the first is simplest, but not guaranteed to work cross browser, as it isn't semantically correct:
<a href="popup.html" target="_blank">Pop Me Up</a>
For example, I use FF and new windows open in new tabs - this link would open in a new tab for me. The best way to do it is using javascript, and I've found a decent method shown below. Don't worry about how it works exactly, but if you're interested then I can explain:
Code:
in <head>
<script type="text/javascript">
function popup(mylink, windowname)
{
if (! window.focus) {
return true;
}
var href;
if (typeof(mylink) == 'string') {
href=mylink;
} else {
href=mylink.href;
}
window.open(href, windowname, 'width=400,height=200,scrollbars=yes');
return false;
}
</script>
in <body>
<a href="popup.html" onClick="return popup(this, 'WIndow Title)">Pop Me Up</a>