Why WTL if MFC exists ?

[fransn]

The advantage of WTL over MFC is that it's much leaner and everything you can do in MFC you can ,with a little more raw api knowledge , do just as easy in WTL. ATL + WTL eliminates the need for MFC. It's easy to switch to WTL from MFC if you just remember that all those MFC calls use almost identical API calls, and use those instead. And besides that a lot of the ATL class definitions are exact copies of the MFC classdefinitions so you can just follow the MFC MSDN on those.
There's a few good walkthroughs on the codeproject site.