to creatre a pop up window

i am working in JSP . i want to create a pop up window. how can i do it.

If you want some help you must provide more information than this.

hi jelin
in following ,look this, if it could help you ?

<script language="JavaScript">
function NewWindow(){
window.open("tianjia.jsp","","height=250,width=400,status=no,location=no,toolbar=no,directories=no,menubar=no");
}
</script>

I am an Chinnese boy,my english is not good.
so sorry!

YEs that could do fine with a button or an image firing an
event calling the method from Java Script to pop up a new
window.

but how do you get it to a precise position, not the upper left corner?

function popup( {
var w = 700;
var h = 400;
var winl = (screen.width-w)/2;
var wint = (screen.height-h)/2;
if (winl < 0) winl = 0;
if (wint < 0) wint = 0;

var page = "yourpage.php";
windowprops = "height="+h+",width="+w+",top="+ wint +",left="+ winl +",location=no,"
+ "scrollbars=yes,menubars=no,toolbars=no,resizable=no,status=yes";
window.open(page, "Popup", windowprops);
}

that works for me. :)