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Project Xanadu

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This article is about a software system. For other meanings see Xanadu (disambiguation)
Project Xanadu was founded by Ted Nelson in 1960 as the original hypertext project. According to the project's website: "Today's popular software simulates paper. The World Wide Web (another imitation of paper) trivializes our original hypertext model with one-way ever-breaking links and no management of version or contents." Wired Magazine called it the "longest-running vaporware story in the history of the computer industry". The first attempt at implementation began in 1960, but it wasn't until 1998 that incomplete software was released. The World Wide Web was in some respects inspired by Xanadu, but falls short of the project's goals.

Contents

History

During his first year as a graduate student at Harvard, Nelson began implementing the system which contained the basic outline of what would become Project Xanadu: a word processor capable of storing multiple versions, and displaying the differences between these versions. Though he did not complete this implementation, a mockup of the system proved sufficient to inspire interest in others.

On top of this basic idea, Nelson wanted to facilitate nonsequential writing, in which the reader could choose his or her own path through an electronic document. He built upon this idea in a paper to the ACM in 1965, calling the new idea "zippered lists". These zippered lists would allow compound documents to be formed from pieces of other documents, a concept he later named transclusion. In 1967, while working for Harcourt, Brace he named his project Xanadu, in honour of the poem Kubla Khan by Samuel Taylor Coleridge.

Ted Nelson published his ideas in his 1974 book Computer Lib/Dream Machines and the 1981 Literary Machines. Computer Lib/Dream Machines is written in a non-sequential fashion: it is a compilation of Nelson's thoughts about computing, among other topics, in no particular order. The books are printed back to back, to be flipped between. Computer Lib contains Nelson's thoughts on topics which angered him, Dream Machines discusses his hopes for the potential of computers to assist the arts.

In 1972, Cal Daniels completed the first demonstration version of the Xanadu software on a computer Nelson had rented for the purpose, though Nelson soon ran out of money. In 1974, with the advent of computer networking, Nelson refined his thoughts about Xanadu into a centralised source of information, calling it a "docuverse".

In the summer of 1979, Nelson led the latest group of his followers, Roger Gregory, Mark Miller and Stuart Greene, to Swarthmore. In a house rented by Gregory, they hashed out their ideas for Xanadu; but at the end of the summer the group went their separate ways. Miller and Gregory created an addressing system based on transfinite numbers which they called tumblers, which allowed any part of a file to be referenced.

The group continued their work, almost to the point of bankruptcy. In 1983, however, Nelson met John Walker, founder of Autodesk, at a conference for the people mentioned in Steven Levy's [[Hackers: Heroes of the Computer Revolution|Hackers]], and the group started working on Xanadu with Autodesk's financial backing.

While at Autodesk, the group, lead by Gregory, completed a version of the software, written in the C programming language, though the software didn't work as well as they wanted. However, this version of Xanadu was successfully demonstrated at the Hacker's Conference and generated considerable interest. Then a newer group of programmers, hired from Xerox PARC, used the problems with this software as justification to rewrite the software in Smalltalk. This effectively split the group into two factions, and the decision to rewrite put a deadline imposed by Autodesk out of the team's reach. In August 1992, Autodesk divested the Xanadu group, which became the Xanadu Operating Company, which struggled due to internal conflicts and lack of investment.

Charles S. Smith, the founder of a company called Memex (the name of the hypertext system designed by Vannevar Bush), hired many of the Xanadu programmers and licensed the Xanadu technology, though Memex soon faced financial difficulties, and the then-unpaid programmers left, taking the computers with them. (The programmers were eventually paid.) At around this time, Tim Berners-Lee was developing the World Wide Web.

In 1998, Nelson released the source code to Xanadu as Project Udanax, in the hope that the techniques and algorithms used could help to overturn some software patents.

The web and Xanadu

Why the World Wide Web became popular instead of Xanadu.

Project Xanadu is more ambitious than the web. Transclusion in Xanadu allows two-way links between any part of documents, whereas the web only has one-way linking to complete documents, or to "anchors" determined by the document author. In Xanadu, links would never be broken, because documents would be distributed in a peer-to-peer fashion, so there would be no need for the ever-present 404 errors. Furthermore, Xanadu addresses document version tracking, while the web doesn't. The web was easy to implement on top of existing file systems, and can be added to by autonomous individuals, while Xanadu is more difficult to implement, relying on cooperation.

Project Xanadu related projects under development

References

External links

 

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