First, the testing environment we will use here is Windows XP Professional (with IIS installed), Visual Studio 2005.  Second, we assume that you have installed the three components of the ASP.ET AJAX framework: ASP.NET AJAX Essential Components, ASP.NET AJAX Futures January CTP, and ASP.NET AJAX Control Toolkit (although not very necessary, but I highly recommend installing it for related comparison).  Third, to follow along with the examples, you need to download the source files accompanying this article (see the downloads section at the end of the article).