The author of this article suggests that to refresh Web pages and online library catalogs in a more pleasing way, Ajax, an acronym for Asynchronous JavaScript and XML, should be used. Ajax is the way to use Web technologies that work together to refresh sections of Web pages to allow almost instant responses to user input. This article describes how Ajax works and its applications. The core of the article shows how to build a very simple Ajax application. It walks the reader through understanding code, the building blocks that make an Ajax application go. The article demonstrates how to set up the interface, work with JavaScript using the XMLHttp Request Object, communicating the request status, putting it all together using the DOM (Document Object Model), and applying CSS (Cascading Style Sheets) for a nice display.