MS-DOS Executive

The Windows shell is the graphical user interface for the Microsoft Windows operating system. Its readily identifiable elements consists of the desktop, the taskbar, the Start menu, the task switcher and the Autoplay feature. On some versions of Windows, it also includes Flip 3D and the charms. However, the Windows shell also implements a shell namespace that enables computer programs running on Windows to access the computer's resources via the hierarchy of shell objects. "Desktop" is the top object of the hierarchy; below it there are a number of files and folders stored on the disk, as well as a number of special folders whose contents are either virtual or dynamically created. Recycle Bin, Libraries, Control Panel, This PC and Network are examples of such shell objects.

The Windows shell, as it is known today, is an evolution of what began with Windows 95, released in 1995. It is intimately identified with File Explorer, a Windows component that can browse the whole shell namespace.

Windows Desktop is a full-screen window rendered behind all other windows. It hosts the user's wallpaper and an array of computer icons representing:

Starting with Windows Vista and Windows 7 (and the corresponding versions of Windows Server), Windows Desktop Gadgets may appear on the desktop. These gadgets are discontinued in newer versions of Windows and Windows Server, starting with Windows 8.

Windows taskbar is a toolbar-like element that by default, appears as a horizontal bar at the bottom of the desktop. It may be relocated to the top, left or right edges of the screen. Starting with Windows 98, its size can be changed. The taskbar can be configured to stay on top of all applications or to collapse and hide when it is not used. Depending on the version of operating system installed, the following elements may appear on the taskbar respectively from left to right:

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