The Frame:
As the name suggests, the frame is a combination of the building blocks, structure and the borders of an item. The frame gives the "physical" presence to a window. The frame defines the position of an object with regards to the Windows desktop. The frame gives borders to a window, borders which the user can grab to size, move & resize the object. The frame is also a type of desk which holds the tools required on an application.
The application cannot exist without a frame. To provide a frame to an application, you can derive a class from the CFrameWnd.
The MFC provides a mechanism for notifying the views of modifications to a document through the UpdateAllViews member function of the CDocument class. The UpdateAllViews function traverse the list of views attached to the document. The function calls the OnUpdate of the CViewClass . Invalidate (TRUE) in OnUpdate clears the client region of the view and calls the OnDraw()function of the view class. The Document View architecture permits the variables in the document class to be exhibited in the view class using the GetDocument() function in the view class.