In this hour you built two applications using the GDI+ API. The first was a managed application using the .NET Framework and its built-in support for GDI+. The second was a traditional MFC application that used GDI+ for its drawing. You learned how to work with GDI+ to perform painting and also learned an easy optimization technique to remove excessive flicker when painting.
Although you didn't use much of the GDI+ API in this hour, you will use it more in the upcoming hours.