Editing X Window System (section)

===Origin and early development===
{{quote box|<syntaxhighlight lang="email" style="border: none">
From: rws@mit-bold (Robert W. Scheifler)
To: window@athena
Subject: window system X
Date: 19 June 1984 0907-EDT (Tuesday)

I've spent the last couple weeks writing a window
system for the VS100. I stole a fair amount of code
from W, surrounded it with an asynchronous rather
than a synchronous interface, and called it X. Overall
performance appears to be about twice that of W. The
code seems fairly solid at this point, although there are
still some deficiencies to be fixed up.

We at LCS have stopped using W, and are now
actively building applications on X. Anyone else using
W should seriously consider switching. This is not the
ultimate window system, but I believe it is a good
starting point for experimentation. Right at the moment
there is a CLU (and an Argus) interface to X; a C
interface is in the works. The three existing
applications are a text editor (TED), an Argus I/O
interface, and a primitive window manager. There is
no documentation yet; anyone crazy enough to
volunteer? I may get around to it eventually.

Anyone interested in seeing a demo can drop by
NE43-531, although you may want to call 3-1945
first. Anyone who wants the code can come by with a
tape. Anyone interested in hacking deficiencies, feel
free to get in touch.
</syntaxhighlight>|The email in which X was introduced to the [[Project Athena]] community at [[MIT]] in June 1984<ref>{{cite web
| url = https://www.talisman.org/x-debut.shtml
| title = Debut of X
| publisher = Talisman
| date = 19 June 1984
| access-date = 7 November 2012}}</ref>
}}
[[File:X11R1.jpg|left|thumb|X11R1 running on a Sun machine]]
The original idea of X emerged at MIT in 1984 as a collaboration between [[Jim Gettys]] (of [[Project Athena]]) and [[Bob Scheifler]] (of the [[MIT Laboratory for Computer Science]]). Scheifler needed a usable display environment for debugging the Argus system. [[Project Athena]] (a joint project between [[Digital Equipment Corporation|DEC]], MIT and [[IBM]] to provide easy access to computing resources for all students) needed a platform-independent graphics system to link together its heterogeneous multiple-vendor systems; the window system then under development in [[Carnegie Mellon University]]'s [[Andrew Project]] did not make licenses available, and no alternatives existed.

The project solved this by creating a protocol that could both run local applications and call on remote resources. In mid-1983 an initial port of [[W Window System|W]] to Unix ran at one-fifth of its speed under V; in May 1984, Scheifler replaced the [[Synchronization (computer science)|synchronous]] [[protocol (computing)|protocol]] of W with an [[wikt:asynchronous|asynchronous]] protocol and the display lists with immediate mode graphics to make X version 1. X became the first windowing system environment to offer true hardware independence and vendor independence.

Scheifler, Gettys and Ron Newman set to work and X progressed rapidly. They released Version 6 in January 1985. DEC, then preparing to release its first [[Ultrix]] workstation, judged X the only windowing system likely to become available in time. DEC engineers ported X6 to DEC's QVSS display on [[MicroVAX]].

In the second quarter of 1985, X acquired [[X11 color names|color]] support to function in the DEC [[VAXstation]]-II/GPX, forming what became version 9.

A group at [[Brown University]] ported version 9 to the [[IBM RT PC]], but problems with reading unaligned data on the RT forced an incompatible protocol change, leading to version 10 in late 1985. X10R1 was released in 1985.<ref>{{Cite web|url=https://ohiostate.pressbooks.pub/graphicshistory/back-matter/cg-historical-timeline/|title=CG Historical Timeline|date=20 June 2017 |last1=Carlson |first1=Wayne E. }}</ref> By 1986, outside organizations had begun asking for X. X10R2 was released in January 1986, then X10R3 in February 1986. Although MIT had licensed X6 to some outside groups for a fee, it decided at this time to license X10R3 and future versions under what became known as the [[MIT License]], intending to popularize X further and, in return, hoping that many more applications would become available. X10R3 became the first version to achieve wide deployment, with both DEC and [[Hewlett-Packard]] releasing products based on it. Other groups ported X10 to [[Apollo Computer|Apollo]] and to [[Sun Microsystems|Sun]] workstations and even to the IBM [[PC/AT]]. Demonstrations of the first commercial application for X (a mechanical computer-aided engineering system from Cognition Inc. that ran on VAXes and remotely displayed on PCs running an X server ported by Jim Fulton and Jan Hardenbergh) took place at the Autofact trade show at that time. The last version of X10, X10R4, appeared in December 1986. Attempts were made to enable X servers as real-time collaboration devices, much as [[Virtual Network Computing]] (VNC) would later allow a desktop to be shared. One such early effort was Philip J. Gust's [[SharedX]] tool.

Although X10 offered interesting and powerful functionality, it had become obvious that the X protocol could use a more hardware-neutral redesign before it became too widely deployed, but MIT alone would not have the resources available for such a complete redesign. As it happened, DEC's [[Western Software Laboratory]] found itself between projects with an experienced team. [[Smokey Wallace]] of DEC WSL and Jim Gettys proposed that DEC WSL build X11 and make it freely available under the same terms as X9 and X10. This process started in May 1986, with the protocol finalized in August. Alpha testing of the software started in February 1987, beta-testing in May; the release of X11 finally occurred on 15 September 1987.<ref>{{Cite newsgroup |title=X Version 11 Released (!!!) |author=Ralph R. Swick|date=Sep 15, 1987|url=https://groups.google.com/g/comp.windows.x/c/NFT3Ax2Io7g/m/Jn37aUty-2QJ |access-date=2024-11-09|newsgroup=comp.windows.x}}</ref>

The X11 protocol design, led by Scheifler, was extensively discussed on open mailing lists on the nascent Internet that were bridged to USENET newsgroups. Gettys moved to California to help lead the X11 development work at WSL from DEC's Systems Research Center, where Phil Karlton and Susan Angebrandt led the X11 sample server design and implementation. X therefore represents one of the first very large-scale distributed [[free and open source software]] projects.