ASP.NET AJAX provides the power of asynchronous JavaScript and XML to your web sites. AJAX makes web pages more responsive and interactive by reducing page refreshes or postbacks. It harnesses the power of client-side JavaScript and the XML HTTP object to provide these features.

Although AJAX is essentially a client-side technique, most of its real-world deployments call for server-side processing. Most commonly, the data manipulated by your web site will reside in some RDBMS on the server. To make AJAX really useful, you need an easy and robust way to deal with this server-side data. Fortunately, ASP.NET AJAX provides a sound infrastructure for doing just that. AJAX communication happens between your browser and the server over the Internet. Naturally, web services can play a significant role in data transport and overall communication between the client and the server.

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