>>>>
>>>>Both C# winforms and ASP.NET (different modules, different puposes) , WCF on and off, and later WPF.
>>>
>>>Thank you.
>>
>>
>>Just to clarify, 'WCF on and off" does not mean 'here and there' but rather 'turned on or turned off.' Like enabled or disabled in code.
>
>WCF is Windows Communication Foundation, right? If so, do I understand correctly that WCF is what you use for connecting to the database?

It's really a way of connecting applications through a service-oriented programming model. Think of exposing and consuming services. This is a very basic, but very clear overview:

http://blah.winsmarts.com/2008-4-What_is_WCF.aspx

Here is MSFT's tutorial:

http://msdn.microsoft.com/en-us/library/ms734712.aspx

More in depth, but quite a process.

Another tutorial:

http://dotnet.org.za/hiltong/pages/Windows-Communication-Foundation-_2800_Indigo_2900_-Hello-World-Tutorial.aspx