The Asynchronous JavaScript And XML (AJAX) model of dynamic HTTP-based applications is quickly taking over the Web. This model provides a more interactive user experience and better performance for Web sites, which no longer send unused bits to each client or need to refresh and retransmit an entire HTML page to update a relatively small portion of the display. Microsoft, recognizing that highly dynamic sites are the future of Web applications, is working to catch up with the AJAX movement by offering a free toolkit called Atlas.

The basic idea behind Atlas is to simplify the AJAX model by providing a set of built-in classes that your ASP.NET pages can leverage to implement AJAX on your site without needing to write a lot of custom code to detect the unique requirements of each client browser. With Atlas, instead of writing the client scripts to enable client callback functions, you drag and drop callback-enabled controls onto your Web page, and the integrated development environment (IDE) handles the underlying calls. Thus, you can start working with callback-enabled pages as easily as you work with server-side callbacks. For detailed information about Atlas, see http://atlas.asp.net.