You use the ABL MDI (multiple document interface) Form when you want a parent form for one or more child forms.
The ABL MDI Form includes a menu bar containing common menus (File, Edit, View, Tools, Windows, Help) and a toolbar containing common command buttons (New, Open, Save, Print, PrintPreview, and Help). Some of the menu items and command buttons include pre-coded event subscriptions and logic. The ABL MDI Form also includes a status bar at the bottom.