One of the least user friendly features of most websites is forms. The longer the form, the more annoying it gets. However, a new technology called AJAX (that has nothing to do with household cleansers!) can help.
XML in the Browser: Submitting forms using AJAX - What's Out There Now (Page 2 of 6 )
Both Google and Amazon have been pioneers in developing AJAX applications. Google's GMail, Suggest, and Google Maps all use AJAX in one way or another to make the Web user interface more like a desktop application.
The documentation for the request object is a little slim, and assumes a certain amount of knowledge of at least HTTP in order to get the most out of it. This article will attempt to lay out as many specifics about the use of XMLHTTPRequest as possible to enable you to use it to its full potential, with a focus on how to use it with forms.
var doc = null
if (typeof window.ActiveXObject != 'undefined' )
doc = new ActiveXObject("Microsoft.XMLHTTP");
doc.onreadystatechange = displayState;
doc = new XMLHttpRequest();
doc.onload = displayState;
A function called displayState is called when the readystate changes or, in the case of the non-Active X object, the onload event is fired. Aside from these differences, everything is cross browser compatible. Except for one thing.