Editing X Window System (section)

==History==
===Predecessors===
Several bitmap display systems preceded X. From [[Xerox]] came the [[Xerox Alto|Alto]] (1973) and the [[Xerox Star|Star]] (1981). From [[Apollo Computer]] came [[Domain/OS#User interface|Display Manager]] (1981). From [[Apple Inc.|Apple]] came the [[Apple Lisa|Lisa]] (1983) and the [[Macintosh 128K|Macintosh]] (1984). The [[Unix]] world had the [[Andrew Project]] (1982) and [[Rob Pike]]'s [[Blit (computer terminal)|Blit]] terminal (1982).

Carnegie Mellon University produced a remote-access application called Alto Terminal, that displayed overlapping windows on the Xerox Alto, and made remote hosts (typically DEC VAX systems running Unix) responsible for handling window-exposure events and refreshing window contents as necessary.

X derives its name as a successor to a pre-1983 window system called [[W Window System|W]] (the letter preceding X in the [[English alphabet]]). W ran under the [[V (operating system)|V operating system]]. W used a network protocol supporting terminal and graphics windows, the server maintaining display lists.

===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.

===The MIT X Consortium and the X Consortium, Inc.===
By the late 1980s X was, [[Simson Garfinkel]] wrote in 1989, "Athena's most important single achievement to date". DEC reportedly believed that its development alone had made the company's donation to MIT worthwhile. Gettys joined the design team for the [[VAXstation 2000]] to ensure that X—which DEC called [[DECwindows]]—would run on it, and the company assigned 1,200 employees to port X to both Ultrix and VMS.<ref name="garfinkel19881112">{{cite news | url=http://simson.net/clips/1989/1989.TechRev.Athena.pdf | title=A Second Wind for Athena | work=Technology Review | date=November–December 1988 | access-date=25 January 2016 | author=Garfinkel, Simson L. | author-link=Simson Garfinkel}}</ref><ref name="garfinkel19890506">{{cite news | url=http://simson.net/clips/1989/1989.TechRev.Athena.pdf | title=Ripples Across the Academic Market | work=Technology Review | date=May–June 1989 | access-date=25 January 2016 | author=Garfinkel, Simson L. | pages=9–13 | author-link=Simson Garfinkel}}</ref> By 1990 IBM and [[Motorola]] announced their own X terminals. [[Bill Joy]] of [[Sun Microsystems]]—which made [[diskless workstations]] competing with X terminals—argued that X was technically flawed and could overwhelm networks.<ref name="marshall19900326">{{Cite magazine |last=Marshall |first=Martin |date=1990-03-26 |title=X Window Terminals: Pro and Con |url=https://books.google.com/books?id=1DsEAAAAMBAJ&pg=PT88#v=onepage&q&f=true |access-date=2025-04-12 |magazine=InfoWorld |page=36, 40}}</ref>

In 1987, with the success of X11 becoming apparent, MIT wished to relinquish the stewardship of X, but at a June 1987 meeting with nine vendors, the vendors told MIT that they believed in the need for a neutral party to keep X from fragmenting in the marketplace. In January 1988, the ''MIT X Consortium'' formed as a non-profit vendor group, with Scheifler as director, to direct the future development of X in a neutral atmosphere inclusive of commercial and educational interests.

Jim Fulton joined in January 1988 and [[Keith Packard]] in March 1988 as senior [[programmers|developers]], with Jim focusing on [[Xlib]], [[Computer font|fonts]], window managers, and utilities; and Keith re-implementing the server. Donna Converse, [[Chris D. Peterson]], and Stephen Gildea joined later that year, focusing on toolkits and widget sets, working closely with Ralph Swick of MIT Project Athena. The MIT X Consortium produced several significant revisions to X11, the first (Release 2{{snd}}X11R2) in February 1988. Jay Hersh joined the staff in January 1991 to work on the [[PHIGS|PEX]] and X113D functionality. He was followed soon after by Ralph Mor (who also worked on PEX) and Dave Sternlicht. In 1993, as the MIT X Consortium prepared to depart from MIT, the staff were joined by R. Gary Cutbill, Kaleb Keithley, and David Wiggins.<ref name=xcoreext>Robert W. Scheifler and James Gettys: X Window System: Core and extension protocols: X version 11, releases 6 and 6.1, Digital Press 1996, {{ISBN|1-55558-148-X}}</ref>

[[File:CDE Application Builder.png|thumb|[[Common Desktop Environment]]]]

In 1993, the X Consortium, Inc. (a non-profit corporation) formed as the successor to the MIT X Consortium. It released X11R6 on 16 May 1994. In 1995 it took on the development of the [[Motif (software)|Motif]] toolkit and of the [[Common Desktop Environment]] for Unix systems. The X Consortium dissolved at the end of 1996, producing a final revision, X11R6.3, and a legacy of increasing commercial influence in the development.<ref>[https://archive.today/20120524185840/http://www.advogato.org/article/844.html Financing Volunteer Free Software Projects] 10 June 2005</ref><ref>[http://www.usenix.org/publications/library/proceedings/usenix2000/invitedtalks/gettys_html/ Lessons Learned about Open Source] 2000</ref>

===The Open Group===
In January 1997, the X Consortium passed stewardship of X to [[The Open Group]], a vendor group formed in early 1996 by the merger of the [[Open Software Foundation]] and [[X/Open]].

The Open Group released X11R6.4 in early 1998. Controversially, X11R6.4 departed from the traditional liberal licensing terms, as the Open Group sought to assure funding for the development of X, and specifically cited [[XFree86]] as not significantly contributing to X.<ref>{{cite web |title=X Statement |url-status=dead |url=https://lwn.net/1998/0409/xstate.html |archive-url=https://web.archive.org/web/20210224185608/https://lwn.net/1998/0409/xstate.html |date=2 April 1998 |archive-date=24 Feb 2021 |access-date=28 Jan 2024 }}</ref> The new terms would have made X no longer [[free software]]: zero-cost for noncommercial use, but a fee otherwise. After XFree86 seemed poised to [[fork (software)|fork]],<ref>{{cite web|date=6 December 1998|title=XFree86(TM): Press Release|url=http://www.xfree86.org/news/pr-980407.html|url-status=dead|archive-url=https://web.archive.org/web/19981206040516/http://www.xfree86.org/news/pr-980407.html|archive-date=6 December 1998|access-date=7 February 2017}}</ref> the Open Group [[Software relicensing|relicensed]] X11R6.4 under the traditional license in September 1998.<ref>{{cite web|last=Browne|first=Christopher|title=X11R6.4 Sample Implementation Changes and Concerns|url=http://cbbrowne.com/info/x11r6.4.html|url-status=dead|archive-url=https://web.archive.org/web/20080601035445/http://cbbrowne.com/info/x11r6.4.html|archive-date=1 June 2008|website=Christopher Browne's Web Pages}}</ref> The Open Group's last release came as X11R6.4 patch 3.

===X.Org and XFree86===
[[XFree86]] originated in 1992 from the [[X386]] server for [[IBM PC compatible]]s included with X11R5 in 1991, written by Thomas Roell and Mark W. Snitily and donated to the MIT X Consortium by Snitily Graphics Consulting Services (SGCS). XFree86 evolved over time from just one port of X to the leading and most popular implementation and the ''de facto'' standard of X's development.<ref name="xfree86.org">{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2004-February/003945.html |title=Re: Announcement: Modification to the base XFree86(TM) license. |date=2 February 2004 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Gettys |first=Jim |author-link=Jim Gettys |language=en |archive-url=https://web.archive.org/web/20050907093907/http://www.xfree86.org/pipermail/forum/2004-February/003945.html |archive-date=7 September 2005}}</ref>

In May 1999, The Open Group formed X.Org. X.Org supervised the release of versions X11R6.5.1 onward. X development at this time had become moribund;<ref>{{cite interview |last=Swales |first=Steve |interviewer-last=Mitchell |interviewer-first=Robert |title=Q&A: The X Factor |work=Computerworld |date=4 February 2002 |publisher=IDG Communications |quote=The stewards of X really dribbled away to almost nothing about five or six years ago. It wasn't really keeping pace with the technology. |url=https://www.computerworld.com/article/2586955/q-a--the-x-factor.html |url-status=live |archive-url=https://web.archive.org/web/20210626035538/https://www.computerworld.com/article/2586955/q-a--the-x-factor.html |archive-date=26 June 2021}}</ref> most technical innovation since the X Consortium had dissolved had taken place in the XFree86 project.<ref>{{cite web |last=Packard |first=Keith |author-link=Keith Packard |language=en |date=1999 |title=The Evolution of the X Server Architecture |url=https://keithp.com/~keithp/talks/Xarchitecture/Talk.htm |url-status=live |archive-url=https://web.archive.org/web/20210626041817/https://keithp.com/~keithp/talks/Xarchitecture/Talk.htm |archive-date=26 June 2021}}</ref> In 1999, the XFree86 team joined X.Org as an honorary (non-paying) member,<ref>{{cite mailing list |url=http://xfree86.org/pipermail/forum/2003-March/000418.html |title=A Call For Open Governance Of X Development |date=23 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Wexelblat |first=David |language=en |archive-url=https://web.archive.org/web/20050212012732/http://xfree86.org/pipermail/forum/2003-March/000418.html |archive-date=12 February 2005}}</ref> encouraged by various hardware companies<ref>{{cite web |title=XFree86 joins X.Org as Honorary Member |date=1 December 1999 |url=https://slashdot.org/story/99/12/01/1342251/xfree86-joins-xorg-as-honorary-member |website=Slashdot |url-status=live |archive-url=https://web.archive.org/web/20210626234537/https://slashdot.org/story/99/12/01/1342251/xfree86-joins-xorg-as-honorary-member |archive-date=26 June 2021}}</ref>{{failed verification|date=June 2021|reason=Source says nothing about hardware companies.}} interested in using XFree86 with Linux and in its status as the most popular version of X.

By 2003, while the popularity of Linux (and hence the installed base of X) surged, X.Org remained inactive,<ref>{{cite mailing list |url=http://xfree86.org/pipermail/forum/2003-April/003127.html |title=Another teleconference partial edited transcript |date=13 April 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Harris |first=Mike |language=en |archive-url=https://web.archive.org/web/20050212013335/http://xfree86.org/pipermail/forum/2003-April/003127.html |archive-date=12 February 2005}}</ref> and active development took place largely within XFree86. However, considerable dissent developed within XFree86. The XFree86 project suffered from a perception of a far too [[The Cathedral and the Bazaar|cathedral]]-like development model; developers could not get [[Concurrent Versions System|CVS]] commit access<ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-March/002018.html |title=Keith Packard issue |date=20 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Nolden |first=Ralf |language=en |archive-url=https://web.archive.org/web/20050212013349/http://www.xfree86.org/pipermail/forum/2003-March/002018.html |archive-date=12 February 2005}}</ref><ref>{{cite mailing list |url=https://www.mail-archive.com/devel@xfree86.org/msg03816.html |title=Cygwin/XFree86 - No longer associated with XFree86.org |date=27 October 2003 |access-date=26 June 2021 |mailing-list=devel@xfree86.org |last=Hunt |first=Harold |language=en |archive-url=https://web.archive.org/web/20210626030145/https://www.mail-archive.com/devel@xfree86.org/msg03816.html |archive-date=26 June 2021 |url-status=live}}</ref> and vendors had to maintain extensive [[patch (computing)|patch]] sets.<ref>{{cite web |last=Harris |first=Mike |title=9 Jan 2003 |date=9 January 2003 |url=http://www.advogato.org/person/mharris/diary.html?start=5 |archive-url=https://web.archive.org/web/20090214100029/http://www.advogato.org/person/mharris/diary.html?start=5 |archive-date=14 February 2009 |language=en}}</ref> In March 2003, the XFree86 organization expelled Keith Packard, who had joined XFree86 after the end of the original MIT X Consortium, with considerable ill feeling.<ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-March/001997.html |title=Invitation for public discussion about the future of X |date=20 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last1=Dawes |first1=David |author-link1=David Dawes |last2=Cutshaw |first2=Robin |last3=Evans |first3=Marc |last4=Murphey |first4=Rich |last5=Tombs |first5=Jon |last6=Wexelblat |first6=David |language=en |archive-url=https://web.archive.org/web/20050212013104/http://www.xfree86.org/pipermail/forum/2003-March/001997.html |archive-date=12 February 2005}}</ref><ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-March/002165.html |title=A Call For Open Governance Of X Development |date=21 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Packard |first=Keith |author-link=Keith Packard |language=en |archive-url=https://web.archive.org/web/20050212012809/http://www.xfree86.org/pipermail/forum/2003-March/002165.html |archive-date=12 February 2005}}</ref><ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-April/003016.html |title=Notes from a teleconference held 2003-3-27 |date=3 April 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Packard |first=Keith |author-link=Keith Packard |language=en |archive-url=https://web.archive.org/web/20050212013506/http://www.xfree86.org/pipermail/forum/2003-April/003016.html |archive-date=12 February 2005}}</ref>

X.Org and XFree86 began discussing a reorganisation suited to properly nurturing the development of X.<ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-March/000554.html |title=A Call For Open Governance Of X Development |date=24 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Swales |first=Steve |language=en |archive-url=https://web.archive.org/web/20041222151738/http://www.xfree86.org/pipermail/forum/2003-March/000554.html |archive-date=22 December 2004}}</ref><ref>{{cite mailing list |url=http://www.xfree86.org/pipermail/forum/2003-March/002415.html |title=A Call For Open Governance Of X Development |date=23 March 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Wexelblat |first=David |language=en |archive-url=https://web.archive.org/web/20050106075606/http://www.xfree86.org/pipermail/forum/2003-March/002415.html |archive-date=6 January 2005}}</ref><ref>{{cite mailing list |url=http://xfree86.org/pipermail/forum/2003-April/003144.html |title=Discussing issues |date=14 April 2003 |access-date=26 June 2021 |mailing-list=forum@xfree86.org |last=Pennington |first=Havoc |author-link=Havoc Pennington |language=en |archive-url=https://web.archive.org/web/20041227204437/http://xfree86.org/pipermail/forum/2003-April/003144.html |archive-date=27 December 2004}}</ref> Jim Gettys had been pushing strongly for an open development model since at least 2000.<ref>{{cite conference |url=https://www.usenix.org/legacy/publications/library/proceedings/usenix2000/invitedtalks/gettys_html/Talk.htm |title=Lessons Learned about Open Source |first=Jim |last=Gettys |author-link=Jim Gettys |date=22 June 2000 |conference=USENIX Annual Technical Conference |url-status=live |archive-url=https://web.archive.org/web/20210627002335/https://www.usenix.org/legacy/publications/library/proceedings/usenix2000/invitedtalks/gettys_html/Talk.htm |archive-date=27 June 2021 |language=en}}</ref> Gettys, Packard and several others began discussing in detail the requirements for the effective governance of X with open development.

Finally, in an echo of the X11R6.4 licensing dispute, XFree86 released version 4.4 in February 2004 under a more restrictive license which many projects relying on X found unacceptable.<ref>{{cite web |title=XFree86 4.4: List of Rejecting Distributors Grows |website=Slashdot |date=18 February 2004 |url=https://yro.slashdot.org/story/04/02/18/131223/xfree86-44-list-of-rejecting-distributors-grows |language=en |url-status=live |archive-url=https://web.archive.org/web/20210627002833/https://yro.slashdot.org/story/04/02/18/131223/xfree86-44-list-of-rejecting-distributors-grows |archive-date=27 June 2021}}</ref> The added clause to the license was based on the original [[BSD license]]'s advertising clause, which was viewed by the [[Free Software Foundation]] and [[Debian]] as incompatible with the [[GNU General Public License]].<ref name="dwheeler.com">{{cite web |last=Wheeler |first=David A. |title=Make Your Open Source Software GPL-Compatible. Or Else. |date=16 February 2014 |orig-date=6 May 2002 |language=en |url=https://dwheeler.com/essays/gpl-compatible.html#xfree86 |url-status=live |archive-url=https://web.archive.org/web/20210126063248/https://dwheeler.com/essays/gpl-compatible.html#xfree86 |archive-date=26 January 2021}}</ref> Other groups saw it as against the spirit of the original X. [[Theo de Raadt]] of [[OpenBSD]], for instance, threatened to [[fork (software)|fork]] XFree86 citing license concerns.<ref name="openbsd">{{cite mailing list |url=https://marc.info/?l=openbsd-misc&m=107696705911864 |title=XFree86 license |date=16 February 2004 |access-date=8 December 2009 |mailing-list=openbsd-misc |last=de Raadt |first=Theo |author-link=Theo de Raadt |language=en |archive-url=https://web.archive.org/web/20190118221625/https://marc.info/?l=openbsd-misc&m=107696705911864&w=2 |archive-date=18 January 2019 |url-status=live}}</ref> The license issue, combined with the difficulties in getting changes in, left many feeling the time was ripe for a fork.<ref>{{cite web |last=Boykin |first=Oscar |title=X Marks the Spot: Looking back at X11 Developments of Past Year |date=25 February 2004 |website=OSNews |language=en |url=https://www.osnews.com/story/6157/x-marks-the-spot-looking-back-at-x11-developments-of-past-year/ |url-status=live |archive-url=https://web.archive.org/web/20210627030537/https://www.osnews.com/story/6157/x-marks-the-spot-looking-back-at-x11-developments-of-past-year/ |archive-date=27 June 2021}}</ref>

===The X.Org Foundation===
In early 2004, various people from X.Org and freedesktop.org formed the [[X.Org Foundation]], and the Open Group gave it control of the <code>x.org</code> [[domain name]]. This marked a radical change in the governance of X. Whereas the stewards of X since 1988 (including the prior X.Org) had been vendor organizations, the Foundation was led by software developers and used community development based on the [[The Cathedral and the Bazaar|bazaar]] model,{{citation needed|date=October 2015}} which relies on outside involvement. Membership was opened to individuals, with corporate membership being in the form of sponsorship. Several major corporations such as [[Hewlett-Packard]] currently{{timeframe|date=February 2024}} support the X.Org Foundation.

The Foundation takes an oversight role over X development: technical decisions are made on their merits by achieving rough consensus among community members. Technical decisions are not made by the board of directors; in this sense, it is strongly modelled on the technically non-interventionist [[GNOME Foundation]]. The Foundation employs no developers.
The Foundation released X11R6.7, the [[X.Org Server]], in April 2004, based on XFree86 4.4RC2 with X11R6.6 changes merged. Gettys and Packard had taken the last version of XFree86 under the old license and, by making a point of an open development model and retaining GPL compatibility, brought many of the old XFree86 developers on board.<ref name="dwheeler.com"/>

While X11 had received extensions such as OpenGL support during the 1990s, its architecture had remained fundamentally unchanged during the decade. In the early part of the 2000s, however, it was overhauled to resolve a number of problems that had surfaced over the years, including a "flawed" [[Computer font|font]] architecture, a 2D graphics system "which had always been intended to be augmented and/or replaced", and [[Latency (engineering)|latency]] issues.<ref>{{cite conference |last1=Gettys |first1=James |first2=Keith |last2=Packard |title=The (Re) Architecture of the X Window System |conference=Proc. Linux Symposium |volume=1 |year=2004 |url=https://keithp.com/~keithp/talks/xarch_ols2004/xarch_ols2004.pdf}}</ref>
X11R6.8 came out in September 2004. It added significant new features, including preliminary support for translucent windows and other sophisticated visual effects, screen magnifiers and thumbnailers, and facilities to integrate with 3D immersive display systems such as Sun's [[Project Looking Glass]] and the [[Croquet project]]. External applications called ''[[compositing window manager]]s'' provide policy for the visual appearance.

On 21 December 2005,<ref>[http://xorg.freedesktop.org/wiki/Other/Press/X11R6970Released?action=show&redirect=PressReleases%2FX11R6970Released X11R6.9 and X11R7.0 Officially Released] 21 December 2005</ref> X.Org released X11R6.9, the monolithic [[source code|source]] tree for legacy users, and X11R7.0, the same source code separated into independent modules, each maintainable in separate projects.<ref>[https://www.x.org/wiki/ModularizationProposal/ Modularization Proposal] 31 March 2005</ref> The Foundation released X11R7.1 on 22 May 2006, about four months after 7.0, with considerable feature improvements.<ref>[https://www.x.org/wiki/ChangesForX11R71/ Proposed Changes for X11R7.1] 21 April 2006</ref>

XFree86 development continued for a few more years, 4.8.0 being released on 15 December 2008.<ref>{{cite web|url=http://www.xfree86.org/releases/rel480.html|title=The Current XFree86 Release: 4.8.0.|work=xfree86.org}}</ref>