A graphical, network-based windowing environment originally developed for Unix and Unix- like operating systems (and since made available for other platforms) at the Massachusetts Institute of Technology; currently, it is under continuous development as an open-source program by the Open Group, a Unix industry consortium.
X (as the X Window system is known to UNIX users) provides the basic windowing services, including fonts and pull-down menus, for graphical UNIX applications. X is designed to function in a network environment.
See desktop environment, GNOME, KDE, UNIX, Unix-like operating system, windowing environment, and window manager, X client, X Protocol, X server.
