As you can see, MFC makes clipboard and drag-and-drop data transfer pretty easy. While you can always write all the code necessary to implement the interfaces (IDataObject, IDropTarget, and IDropSource), using MFC's implementations is much more convenient. While we've looked only at clipboard and drag and drop transfers through IDataObject in this chapter, everything you learn about the IDataObject interface will carry forward to your study of compound documents in the next chapter.