This article applies to ASP.NET 2.0 and Visual Studio 2005. Background Since its early days, ASP.NET has always supported two different ways of authoring server controls: Custom Controls : these are controls written from scratch exclusively using code. Essentially, you write a class which extends Control (directly or indirectly), and you take care of everything. You need to write logic to create child controls that you want to use, and you override the Render method to perform rendering. Typically, you build this control into a redistributable assembly (i.e. a DLL), which can then be used by any ASP.NET applications, simply by placing the assembly in the 'bin' directory of the app (or in the Global Assembly Cache). User Controls : these control...