There were certainly places where ASP.NET would generate client-side JavaScript, most notably in the validation controls and more recently with the Web Part infrastructure, but it was rarely more than a simple translation of server-side properties into client-side behavior-you as the developer didn't have to think about interacting with the client until you received the next POST request. Developers needing to build more interactive pages with client-side JavaScript and DHTML were left to do it on their own, with some help from the ASP.NET 2.0 script callbacks feature. This has changed completely in the last year.
At the Microsoft Professional Developer's Conference in September 2005, Microsoft unveiled a new add-on to ASP.NET, code-named "Atlas," which was focused entirely on leveraging client-side JavaScript, DHTML, and the XMLHttpRequest object. The goal was to aid developers in creating more interactive AJAX-enabled Web applications.
