X server

X server

[′eks ‚ser·vər]
(computer science)
Software that draws the screen image and handles standard input in an X Windows System; in contrast to typical usage of the term server, an X server is located on the user's computer; the client is the application that is displayed, which may be located on a remote node of the network.

X server

(graphics, operating system)
A process, in an X Window System which controls a bitmap display device and usually also a keyboard and mouse or other pointing device. The X server performs operations on request from client applications, which may be on the same computer or a different computer connected via a network.

Note that typical client-server architectures do input-output on the client and processing on the server whereas in X the terms are reversed as the X server is serving IO rather than processing resources to the application.

If the two computers are not both Unix machines (e.g. one is a Windows machine running VNC) or if a more secure connection is required (e.g. tunneling with ssh), the clients may talk to a proxy X server that forwards the requests to another machine where the real IO takes place.

X server

The software in an X Window system that renders images to the display screen. X servers are the user's desktop or laptop machine. In the early days of X Window, X terminals were widely used, which were hardware dedicated only to X server rendering. See PC X server and X Window. See also Xserve.