Simple event handling uses ChkEvent() and the EVENT_* events.
    Clip-4-Win handles many messages for you.  With window procedures
    you must use the traditional Windows GetMessage(), TranslateMessage(),
    DispatchMessage(), etc. loop and handle more messages yourself.

    Debugging can be harder with window procedures.  See the section on
    the debugger (below).

    Window procedures are the most powerful way of doing things, and very
    close to examples you'll find in books about programming Windows.

    Try using window subclassing if you just need a few of the WM_* messages.