Taskbar Explained

In computing, the taskbar is a term for an application desktop bar which is used to launch and monitor applications. Microsoft incorporated a taskbar in Windows 95 and it has been a defining aspect of Microsoft Windows's graphical user interface ever since. Other desktop environments, such as KDE and GNOME also include a taskbar. Non-Windows platforms may use different terminology, such as Panel or Dock.

Microsoft Windows

In Microsoft Windows, the default location for the taskbar is at the bottom of the screen, and from left to right it contains by default the Start menu button, Quick Launch bar, taskbar buttons and notification area. This has changed in pre-beta versions of the forthcoming Windows 7, which combines the Quick Launch bar and taskbar buttons and introduces Jump Lists.

The taskbar was originally developed as a feature of Windows 95, but it was based on a similar user interface feature called the tray that was developed as part of Microsoft's Cairo project.[1] [2]

With the release of Windows XP, Microsoft changed the behavior of the taskbar to take advantage of Fitts' law.[3]

Taskbar elements


The Windows taskbar can be modified by users in several ways. The position of the taskbar can be changed to appear on any edge of the primary display. Up to and including Windows Server 2008, the taskbar is constrained to single display, although third-party utilities such as UltraMon allow it to span multiple displays. When the taskbar is displayed vertically on versions of Windows prior to Windows Vista, the Start menu button will only display the text "Start" or translated equivalent if the taskbar is wide enough to show the full text.[13] However, the edge of the taskbar (in any position) can be dragged to control its height (width for a vertical taskbar); this is especially useful for a vertical taskbar to show window titles next to the window icons.

Users can resize the height (or width when displayed vertically) of the taskbar up to half of the display area. To avoid inadverdent resizing or repositioning of the taskbar, Windows XP Home Edition locks the taskbar by default.[4] [14] When unlocked, "grips" are displayed next to the movable elements which allow grabbing with the mouse to move and size. These grips slightly decrease amount of available space in the taskbar.

The taskbar as a whole can be hidden until it the mouse pointer is moved to the display edge, or has keyboard focus.

Desktop toolbars

Other toolbars, known as "Deskbands", may be added to the taskbar.[15] Windows includes the following deskbands but does not display them by default (except the Quick Launch toolbar in certain versions and configurations).

In addition to deskbands, Windows supports "Application Desktop Toolbars" (also called "appbands") that supports creating additional toolbars that can dock to any side of the screen, and cannot be overlaid by other applications.[16]

Users can add additional toolbars that display the contents of folders. The display for toolbars that represent folder items (such as Links, Desktop and Quick Launch) can be changed to show large icons and the text for each item. Prior to Windows Vista, the Desktop Toolbars could be dragged off the taskbar and float independently, or docked to a display edge. Windows Vista greatly limited, but did not eliminate the ability to have desktop toolbar not attached to the taskbar[17] .

Other desktop environments

Acorn Computers

An early implementation of the taskbar concept is seen in Acorn Computers Arthur operating system, which was released in 1987 for their Acorn Archimedes computer. It is called the Iconbar and remains an essential part of Arthur's succeeding RISC OS operating system. The Iconbar holds icons which represent mounted disc drives and RAM discs, running applications and system utilities. These icons have their own context-sensitive menus and support drag and drop behaviour.

Unix and Unix-like


In various KDE distributions, the taskbar is run by the Kicker program, which shows rectangular panels that can contain applets, one of which is the taskbar. Applets can be arbitrarily relocated, for instance, the notification area can be moved away from the taskbar. The bar can be placed not only at the bottom, but also at the top or (vertically) at the left or the right and its size can be altered (from 24 to 256 pixels), as well as the length in % of the screen size. And several other bars with various specific functions can be added in different locations, eg, one bar at the left and one at the right or even overlapping (one fixed and one with automatic hiding).Since KDE4, the taskbar is implemented as a plasmoid.


Similarly, the GNOME desktop environment uses its own type of taskbar, known as panels (the program responsible for them is therefore called gnome-panel). By default, GNOME usually contains two full-width panels at the top and bottom of the screen. The top panel usually contains navigation menus labelled Applications, Places, and System in that order. These menus hold links to common applications, areas of the file system, and system preferences and administration utilities, respectively. The top panel usually contains a clock and notification area, which can double as a sort of dock, as well.The bottom panel is commonly empty by default, other than a set of buttons to navigate between desktops and a button to minimize all windows and show the desktop, due to its use in the navigation between windows (windows minimize to the bottom panel by default).

These panels can be populated with other customizable menus and buttons, including new menus, search boxes, and icons to perform quick-launch like functions. Other applications can also be attached to the panels, and the contents of the panels can be moved, removed, or configured in other ways.

Other Unix environments

There are many programs that offer standalone taskbars for desktop environments or window managers without one. Example include pypanel, fbpanel, perlpanel, and others.

Apple Macintosh computers

The Dock, as featured in Mac OS X and its predecessor NEXTSTEP, is also a kind of taskbar. The Mac OS X Dock is application-oriented instead of window-oriented. Each running application is represented by one icon in the Dock regardless of how many windows it has on screen. A textual menu can be opened by right-clicking on the dock icon that gives access to an application's windows, among other functions determined by the app. Minimized windows also appear in the dock, in the rightmost section, represented by a graphical thumbnail. The trash can is also represented in the Dock, as a universal metaphor for deletion. For example, dragging selected text to the trash should remove the text from the document and create a clipping file in the trash.

See also

Notes and References

  1. Web site: The Windows 95 User Interface: A Case Study in Usability Engineering. Kent Sullivan. April 17, 1996. CHI 96 Design Briefs. 2008-10-22.
  2. Web site: Why do some people call the taskbar the "tray"?. Chen. Raymond. Raymond Chen. September 10, 2003. 2008-04-20. The Old New Thing. Microsoft.
  3. Web site: Giving You Fitts. Harris. Jensen. August 22, 2006. 2008-01-14. Jensen Harris: An Office User Interface Blog. Microsoft.
  4. Web site: Differences with Windows XP Home Edition. November 3, 2005. 2008-04-20. Windows XP Resource Kit. Microsoft.
  5. http://msdn.microsoft.com/en-us/library/aa511448.aspx Windows Vista Developer Center - The Windows desktop
  6. Web site: How to remove items from the notification area in Windows 2000. November 1, 2006. 2008-10-21.
  7. Web site: http://msdn.microsoft.com/en-us/library/aa511448.aspx. Microsoft Developer Network.
  8. Web site: How To Manipulate Icons in the System Tray with Visual Basic. 2004-07-15. 2009-01-23.
  9. Web site: How to use the System Tray directly from Visual Basic. 2006-09-26. 2009-01-23.
  10. Web site: System Tray Icon Sample. 2009-01-23.
  11. Web site: System Tray Balloon Tips and Freeing Resources Quickly in .NET. 2002-11. 2009-01-23.
  12. Web site: Microsoft Time Zone. 2004-10-20. 2009-01-23.
  13. Web site: When I dock my taskbar vertically, why does the word "Start" disappear?. Chen. Raymond. Raymond Chen. September 20, 2003. 2008-04-20. The Old New Thing. Microsoft.
  14. Web site: Cannot Move or Resize the Taskbar or Any Toolbars on the Taskbar (MSKB279774). January 25, 2006. 2008-04-20. Knowledge Base. Microsoft.
  15. Web site: Notification Area. Windows Vista User Experience Guidelines. Microsoft.
  16. Web site: Using Application Desktop Toolbars. Microsoft.
  17. http://windowshelp.microsoft.com/Windows/en-US/Help/5cca95d3-219a-436b-b016-831296b821ad1033.mspx Create a shortcut toolbar on the desktop
  18. http://support.microsoft.com/?id=226111 DeskBar Options Tab in Taskbar Properties Is Not Functional