The Visual Basic Windows Form class is a descendant of the Control class. The inheritance trail is Control
At the same time, Forms have their own special features that set them apart from other kinds of controls. You usually place controls inside a form, but you rarely place a form inside another form. Forms also play a very central role in most Visual Basic applications. They are the largest graphical unit with which the user interacts directly. The user can minimize, restore, maximize, and close forms. They package the content provided by the other controls so that the user can manage them in a meaningful way.
This chapter describes some of the special features of Windows Forms not provided by other objects. It focuses on different ways that typical applications use forms. For example, it explains how to build multiple-document interface (MDI) applications, custom dialogs, and splash screens.