A client/server system for running a graphical user interface (GUI) that uses windows in a UNIX environment. The X Window System, also known as “X,” was developed jointly by the Massachusetts Institute of Technology (MIT), Stanford, and IBM starting in 1984, and its implementation is standardized by The Open Group. The X Window System is device-independent and provides a multitasking windowing environment for client computers.
The X Window System runs on network-attached workstations and terminals that access UNIX servers or mainframe computers. Elements of the X Window System include the following: