Windows shell

The Windows shell provides users with access to a wide variety of objects necessary for running applications and managing the operating system. The most numerous and familiar of these objects are the folders and files that reside on computer disk drives. There are also a number of virtual objects that allow the user to perform tasks such as sending files to remote printers or accessing the Recycle Bin. The Shell organizes these objects into a hierarchical namespace and provides users and applications with a consistent and efficient way to access and manage objects.

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:

Task switcher is a feature present in Windows 3.0 and all subsequent versions of Windows. It allows a user to cycle through existing application windows by holding down the Alt key and tapping the Tab ↹ key. Starting with Windows 95, as long as the Alt key is pressed, a list of active windows is displayed, allowing the user to cycle through the list by tapping the Tab ↹ key. An alternative to this form of switching is using the mouse to click on a visible portion of an inactive window. However, Alt+Tab ↹ may be used to switch out of a full screen window. This is particularly useful in video games that lock, restrict or alter mouse interactions for the purpose of the game. Starting with Windows Vista, Windows Desktop is included in the list and can be activated this way.

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