window manager

A window manager is computer software that controls the placement and appearance of windows within a windowing system in a graphical user interface.Alternative shells for Microsoft Windows have also emerged. For example, LiteStep can replace the user interface on Windows 95, 98, or NT with an Afterstep style. OS/2 ships with Presentation Manager as the default shell, but third party sources can supply alternatives.
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An X window manager is software that controls the placement and appearance of windows under the X Window System, a windowing system mainly used on Unix-like systems.Unlike the Apple Macintosh and Microsoft Windows platforms, which have historically provided a vendor-controlled, fixed set of ways to control how windows and panes display on a screen, and how the user may interact with them, window management for the X Window System was deliberately kept separate from the software providing the graphical display. The user can choose between various third-party window managers, which differ from one another in several ways, including:customizability of appearance and functionality:textual menus used to start programs and/or change optionsdocks and other graphical ways to start programsmultiple desktops and virtual desktops (desktops larger than the physical monitor size), and pagers to switch between themconsumption of memory and other system resourcesdegree of integration with a desktop environment, which provides a more complete interface to the operating system, and provides a range of integrated utilities and applications.
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<operating system> A part of a window system which arranges windows on a screen. It is responsible for moving and resizing windows, and other such functions common to all applications.
Examples from the X Window System are twm, gwm, olwm.
(1994-12-06)