Editing Windows 9x (section)

===User interface===
{{See also|User interface}}

Users can control a Windows 9x-based system through a [[command-line interface]] (or CLI) or a [[graphical user interface]] (or GUI). The default mode for Windows is usually the graphical user interface, whereas the CLI is available through [[MS-DOS]] windows. The GUI provides a means to control the placement and appearance of individual application windows, and interacts with the window system.

The [[Graphics Device Interface|GDI]], which is a part of the Win32 and Win16 subsystems, is also a module that is loaded in [[user mode]], unlike Windows NT where the GDI is loaded in [[kernel mode]]. [[Alpha compositing]] and therefore [[Transparency (graphic)|transparency]] effects, such as fade effects in menus, are not supported by the [[Graphics Device Interface|GDI]] in Windows 9x, unlike with Windows NT releases since Windows 2000.

The default user interface of the GUI is [[Windows Explorer]]; however, a variety of additional [[List of alternative shells for Windows|Windows shell replacement]]s exist. Other GUIs include [[LiteStep]], bbLean and [[Program Manager]].