# The Mother of All Demos
**The Mother of All Demos** was a 90-minute live public demonstration of the oN-Line System (NLS), given by Douglas C. Engelbart and 17 researchers of the Augmentation Research Center at [SRI International](https://www.edgepedia.org/sri-international) on December 9, 1968, at the Fall Joint Computer Conference in San Francisco. It was the public debut of the computer mouse and showed, for the first time to a large audience, hypertext with dynamic file linking, overlapping windows, cut-copy-paste editing, shared-screen collaboration between two people at different sites, and video teleconferencing.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [2](https://invention.si.edu/invention-stories/mother-all-demos) Journalist Steven Levy, in his 1994 book *Insanely Great*, hailed the event as "the mother of all demos," a name also attributed to Andy van Dam, a computer scientist who was in the audience.[2](https://invention.si.edu/invention-stories/mother-all-demos) • [3](https://cs.brown.edu/stc/resea/telecollaboration/engelbart.html)
| Key fact | Detail |
|---|---|
| Date and venue | December 9, 1968, Fall Joint Computer Conference, San Francisco; 90-minute plenary session[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [2](https://invention.si.edu/invention-stories/mother-all-demos) |
| Presenters | Douglas C. Engelbart on stage, with 17 Augmentation Research Center researchers contributing; lead engineer Bill English masterminded the production[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [4](https://dougengelbart.org/content/view/209/) |
| Debuts | Computer mouse, hypertext with object addressing and dynamic file linking, overlapping windows, shared-screen two-site collaboration with audio and video[1](https://www.dougengelbart.org/mousesite/1968Demo.html) |
| Link | Two video channels over a microwave link of about 30 miles from SRI in Menlo Park; commands returned over a leased telephone line through a homemade 2,400 baud modem[2](https://invention.si.edu/invention-stories/mother-all-demos) |
| Computer | SDS 940 time-sharing system using the Project GENIE time-sharing system from UC Berkeley, with a 96-million-character disc file[5](https://bitsavers.org/pdf/sri/arc/1968/Development_of_a_Multidisplay_Time-Shared_Computer_Facility_196804.pdf) |
| Development time | Most of what was shown was built from scratch by a handful of researchers in roughly two years[4](https://dougengelbart.org/content/view/209/) |
| Aftermath | Standing ovation; funding declined after 1969; ARC sold to Tymshare in 1977, where NLS became Augment[4](https://dougengelbart.org/content/view/209/) • [6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/) |
## Background: Engelbart and the Augmentation Research Center
[Douglas Engelbart](https://www.edgepedia.org/douglas-engelbart) set out his research program in 1962, arguing that computing machinery could augment human intellect rather than merely automate calculation. With grants from ARPA (won in 1963), NASA, and the [United States Air Force](https://www.edgepedia.org/united-states-air-force), he established the Augmentation Research Center (ARC) at SRI in [Menlo Park, California](https://www.edgepedia.org/menlo-park-california), to build the oN-Line System, NLS.[2](https://invention.si.edu/invention-stories/mother-all-demos) By 1968 the team called the system NLS, short for "online system," in contrast to an "offline system" they dubbed FLS; it was later renamed AUGMENT.[7](https://web.stanford.edu/class/history34q/readings/Engelbart/Engelbart_AugmentWorkshop.html)
The installation behind the demo was an SDS 940 computer designed for time-sharing among multiple users. An April 1968 SRI report describes the facility as running the time-sharing system developed by Project GENIE at the [University of California](https://www.edgepedia.org/university-of-california), Berkeley, backed by a 96-million-character disc-file system.[5](https://bitsavers.org/pdf/sri/arc/1968/Development_of_a_Multidisplay_Time-Shared_Computer_Facility_196804.pdf) • [8](https://www.darpa.mil/node/2094) By 1968 NLS functioned as what [Ars Technica](https://www.edgepedia.org/ars-technica) has called a proto-intranet; the ARPANET itself was not established until late the following year.[9](https://arstechnica.com/information-technology/2018/12/50-years-on-were-living-the-reality-first-shown-at-the-mother-of-all-demos/)
## The technology demonstrated
**The mouse and the interface.** The presentation was the public debut of the computer mouse.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) NLS ran on a radar-like CRT screen with a graphical user interface in which users manipulated text, symbols, and video in a series of overlapping windows.[2](https://invention.si.edu/invention-stories/mother-all-demos) Engelbart described the chord keyset (five-key device typed by pressing key combinations) and the mouse via teleconference during the demo.[2](https://invention.si.edu/invention-stories/mother-all-demos)
**Hypertext and linking.** NLS supported object addressing and dynamic file linking: users clicked hypertext links to jump between related documents. In the demo, Engelbart clicked links on a map of his route home, with stops labeled Library and Drugstore, to pull up associated lists.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [2](https://invention.si.edu/invention-stories/mother-all-demos)
**Collaboration at a distance.** When multiple NLS systems were linked, users could work simultaneously on the same document. Engelbart conferenced in [Bill Paxton](https://www.edgepedia.org/bill-paxton) from Menlo Park, and the two edited the same document together while communicating over the network with audio and video.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [2](https://invention.si.edu/invention-stories/mother-all-demos)
## Staging the demonstration
In March 1968 Engelbart applied for a special 90-minute plenary session at the ACM/IEEE-CS Fall Joint Computer Conference, held in San Francisco.[2](https://invention.si.edu/invention-stories/mother-all-demos) The talk was titled "A Research Center for Augmenting Human Intellect," and Engelbart drove the NLS computer located 30 miles away at SRI from a custom console on stage, with lead engineer [Bill English](https://www.edgepedia.org/bill-english) masterminding the production.[4](https://dougengelbart.org/content/view/209/)
The infrastructure was built for the occasion. English's team placed cameras before two NLS monitors at SRI, beamed two video channels over a microwave link about 30 miles to the auditorium, and sent Engelbart's commands back to Menlo Park over a leased telephone line through a homemade 2,400 baud modem. A four-channel video controller directed what was projected onto the auditorium screen, and 17 ARC teammates contributed to the demo.[2](https://invention.si.edu/invention-stories/mother-all-demos)
## By the numbers
- **Duration:** 90 minutes, live.[1](https://www.dougengelbart.org/mousesite/1968Demo.html)
- **Team:** 17 ARC researchers contributed, in addition to Engelbart.[1](https://www.dougengelbart.org/mousesite/1968Demo.html)
- **Development:** most of the demonstrated capabilities were built from scratch in roughly two years.[4](https://dougengelbart.org/content/view/209/)
- **Link distance:** about 30 miles between the auditorium and SRI in Menlo Park.[2](https://invention.si.edu/invention-stories/mother-all-demos)
- **Command link:** 2,400 baud over a leased telephone line.[2](https://invention.si.edu/invention-stories/mother-all-demos)
- **Audience:** cited estimates range from about 1,000 computer professionals to roughly 2,000 conference-goers.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) • [6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/) • [4](https://dougengelbart.org/content/view/209/)
- **Screen size:** the Smithsonian describes a 20-foot screen; DARPA describes a 22-foot-high screen with video insets.[2](https://invention.si.edu/invention-stories/mother-all-demos) • [8](https://www.darpa.mil/node/2094)
- **Planned ARPANET bandwidth:** in the demo's closing segment Engelbart discussed the planned 1969 ARPA network of 20 computer sites, musing that with a planned bandwidth of 20 KB per second and delay under one-tenth of a second he might repeat the demo from Boston the next year.[1](https://www.dougengelbart.org/mousesite/1968Demo.html)
## Reception, aftermath, and the PARC lineage
The audience erupted into a standing ovation.[4](https://dougengelbart.org/content/view/209/) Attendees who later commented on the event include [Alan Kay](https://www.edgepedia.org/alan-kay), Andy van Dam, and Charles Irby.[4](https://dougengelbart.org/content/view/209/)
The aftermath was less triumphant. In 1969 Bob Taylor left ARPA, ARPA changed its funding policies amid general government belt-tightening, and ARC's funding dried up. Xerox PARC, which Taylor joined, hired ARC members including Bill English, Jeff Rulifson, and Bill Duvall; the bitter joke ran that ARC was a training program for PARC. After the failure of PARC's POLOS project, hypertext links and the emphasis on collaboration were left out of PARC's development stream.[6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/) Xerox debuted the Alto in 1973, five years after the demo.[9](https://arstechnica.com/information-technology/2018/12/50-years-on-were-living-the-reality-first-shown-at-the-mother-of-all-demos/) In 1977 SRI sold the ARC project to Tymshare, where NLS became Augment; Engelbart retired from Tymshare in 1986 and continued his work from offices provided by Logitech.[6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/)
The commercialization of what the demo showed took decades. It was fifteen years before the Apple Macintosh (1984) brought the mouse and GUI to a mass market, and nearly forty years before [Google Docs](https://www.edgepedia.org/google-docs), Sheets, and Slides (2006) popularized shared document editing.[2](https://invention.si.edu/invention-stories/mother-all-demos) In hypertext history, Thierry Bardini, a scholar of Engelbart's lab, identifies two founding cultures: [Ted Nelson](https://www.edgepedia.org/ted-nelson)'s Xanadu Project, aimed at individual literary creativity, and Engelbart's NLS, a support for group collaboration. Randall Trigg's classification of second-generation hypertext systems such as Notecards, Neptune, and Intermedia follows the same split, with network-based systems descended from Xanadu and outline-based systems descended from NLS.[10](https://onlinelibrary.wiley.com/doi/full/10.1111/j.1083-6101.1997.tb00069.x)
## Legacy and the surviving record
The demo's elements map directly onto present-day computing: live videoconferencing, collaborative editing, windows, hypertext, and the mouse were all shown in one session in 1968.[6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/) Bardini's monograph *Bootstrapping* (Stanford University Press) treats Engelbart's SRI lab of the 1960s as the origin of the mouse, the windowed user interface, and hypertext within the wider US computer research community.[11](https://www.sup.org/books/media-studies/bootstrapping)
**Primary records.** The original 90-minute video is held in the Engelbart Collection in Special Collections of Stanford University and has been edited into 35 segments.[1](https://www.dougengelbart.org/mousesite/1968Demo.html) The Internet Archive holds the SRI film of the presentation in three reels.[12](https://archive.org/details/XD300-23_68HighlightsAResearchCntAugHumanIntellect) The companion paper by Engelbart and William K. English appeared in the AFIPS Conference Proceedings of the 1968 Fall Joint Computer Conference, volume 33, December 1968, pages 395 to 410.[4](https://dougengelbart.org/content/view/209/) The Computer History Museum's ARC/NIC archive, brought in by former NIC director Elizabeth "Jake" Feinler, comprises over 300 boxes of documents and hundreds of backup tapes.[6](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/)
**Recent digitization.** The demo's 57th anniversary fell on December 9, 2025; the Doug Engelbart Institute marked it by releasing a new 30-minute highlights version in 12 clips and a new 100-minute interactive chapterized edition. The 50th anniversary in 2018 had been celebrated with major events on three continents.[4](https://dougengelbart.org/content/view/209/)
## References
1. [Doug Engelbart 1968 Demo, Doug Engelbart Institute](https://www.dougengelbart.org/mousesite/1968Demo.html)
2. [The Mother of All Demos, Lemelson Center, Smithsonian Institution](https://invention.si.edu/invention-stories/mother-all-demos)
3. [Douglas Engelbart and 'The Mother of All Demos', Brown University CS](https://cs.brown.edu/stc/resea/telecollaboration/engelbart.html)
4. [Firsts: The Demo, Doug Engelbart Institute](https://dougengelbart.org/content/view/209/)
5. [Development of a Multidisplay, Time-Shared Computer Facility, SRI, April 1968](https://bitsavers.org/pdf/sri/arc/1968/Development_of_a_Multidisplay_Time-Shared_Computer_Facility_196804.pdf)
6. [Net@50: Did Engelbart's "Mother of All Demos" Launch the Connected World?, Computer History Museum](https://computerhistory.org/blog/net-50-did-engelbart-s-mother-of-all-demos-launch-the-connected-world/)
7. [Engelbart workshop remarks, Stanford course reading](https://web.stanford.edu/class/history34q/readings/Engelbart/Engelbart_AugmentWorkshop.html)
8. [The Mother of all Demos, DARPA](https://www.darpa.mil/node/2094)
9. [50 years on, we're living the reality first shown at the "Mother of All Demos", Ars Technica](https://arstechnica.com/information-technology/2018/12/50-years-on-were-living-the-reality-first-shown-at-the-mother-of-all-demos/)
10. [Thierry Bardini (1997). Bridging the Gulfs: From Hypertext to Cyberspace. Journal of Computer-Mediated Communication.](https://onlinelibrary.wiley.com/doi/full/10.1111/j.1083-6101.1997.tb00069.x)
11. [Thierry Bardini. Bootstrapping: Douglas Engelbart, Coevolution, and the Origins of Personal Computing. Stanford University Press.](https://www.sup.org/books/media-studies/bootstrapping)
12. [1968 Demo - FJCC Conference Presentation Reel #1, SRI International, Internet Archive](https://archive.org/details/XD300-23_68HighlightsAResearchCntAugHumanIntellect)
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*Topic: Encyclopedia › Technology and the built world › Computing and digital systems › Computer scientists and computing pioneers (biographies)*
*Initially written Sep 17, 2026 · Reviewed: Oct 15, 2026 · Edited: Oct 15, 2026 · Last review: Oct 15, 2026*
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