MDI (Multiple Document Interface) is a Microsoft Windows programming
interface for creating an application that enables users to work with
multiple documents at the same time. Each document is in a separate
space with its own controls for scrolling. The user can see and work
with different documents such as a spreadsheet, a text document, or a
drawing space by simply moving the cursor from one space to another.
An MDI application is something like the Windows desktop
interface since both include multiple viewing spaces. However, the MDI
viewing spaces are confined to the application's window or client area
. Within the client area, each document is displayed within a separate
child window . MDI applications can be used for a variety of purposes -
for example, working on one document while referring to another
document, viewing different presentations of the same information,
viewing multiple Web sites at the same time, and any task that requires
multiple reference points and work areas at the same time