Two table structures in application memory or in resource files (.RC file-name extension), identify window resources in the IPF library. The help table associates each application window with its corresponding help subtable and the window identifier of its extended help window. The help subtable associates each entry field, menu item and push button within an application window with the window identifier (ID) of its help window. The address of the help table is passed to the application during initialization of the IPF initializing structure (HELPINIT).

When the user requests help on a field, menu bar, or push button in the application window, IPF uses the help subtable associated with the field to find the window ID of the contextual help window for the field. The help subtable also can store optional entries relating to application-specific information.

The maximum size of the help table is 64KB. The number of help subtables is limited to 16 000.

IPF supports two methods of defining help tables and help subtables. They can be allocated in memory, or they can be defined as resources. In either case, the information passed to IPF is identical.