To customize the way Windows Help works with your Help file, you may want to execute a macro when the user enters a topic. Windows Help includes a variety of macros, any of which can be included as a footnote macro. In general, Help macros can be used to:
nModify Help menus and menu functionality.
nModify Help buttons and button functionality.
nModify Help window behavior.
nCreate hypertext links.
nCreate and manipulate text markers.
nAssign a Help macro to a keyboard access key (or key combination).
nStart an application.
nRegister a function within a DLL as a Help macro.
The complete list of macros that Windows Help version 3.1 supports is found in Chapter 15, “Help Macro Reference.” Refer to that chapter for full details about each macro.