Yes, what you are asking for is called AJAX or XMLHttpRequest. You can either use a library like jQuery to simplify making the call (due to cross-browser compatibility issues), or write your own handler.
In jQuery:
$.GET('url.asp', {data: 'here'}, function(data){ /* what to do with the data returned */ })
In plain vanilla javaScript (from w3c):
var xmlhttp;
function loadXMLDoc(url)
{
xmlhttp=null;
if (window.XMLHttpRequest)
{// code for all new browsers
xmlhttp=new XMLHttpRequest();
}
else if (window.ActiveXObject)
{// code for IE5 and IE6
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
if (xmlhttp!=null)
{
xmlhttp.onreadystatechange=state_Change;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
}
else
{
alert("Your browser does not support XMLHTTP.");
}
}
function state_Change()
{
if (xmlhttp.readyState==4)
{// 4 = "loaded"
if (xmlhttp.status==200)
{// 200 = OK
//xmlhttp.data and shtuff
// ...our code here...
}
else
{
alert("Problem retrieving data");
}
}
}