X Window System
The X Window System is a network transparent window system which runs on a wide range of computing and graphics machines. There are two open source implementations of X Window System:
Currently X.org is the default X window system for openSUSE and forms the base for your favorite window manager
- From Wikipedia, the free Encyclopedia, article X Window System, design.
X uses a client–server model: an X server communicates with various client programs. The server accepts requests for graphical output (windows) and sends back user input (from keyboard, mouse, or touchscreen). The server may function as:
- an application displaying to a window of another display system
- a system program controlling the video output of a PC
- a dedicated piece of hardware.
This client–server terminology — the user's terminal being the server and the applications being the clients — often confuses new X users, because the terms appear reversed. But X takes the perspective of the application, rather than that of the end-user: X provides display and I/O services to applications, so it is a server; applications use these services, thus they are clients.
The communication protocol between server and client operates network-transparently: the client and server may run on the same machine or on different ones, possibly with different architectures and operating systems. A client and server can even communicate securely over the Internet by tunneling the connection over an encrypted network session.