Web precursor Xanadu project goes open source
A brilliant collection of ideas that was never going to ship - so is it relevant?
Project Xanadu, a 1960s hypertext vision and the industry's most delayed vapourware, is putting some of its code on the Web as open source with an X11 licence. Ted Nelson, Xanadu's guiding light, invented the terms hypertext and hypermedia in 1963 but failed to develop a working system incorporating it. Despite this, he and his ideas have had a seminal influence on the invention of Lotus Notes (Ozzie Clark acknowledged inspiration from Nelson), and indirectly on HTML and the Web. It is probably best to consider Nelson's xanological structure to be just an abstract idea, rather like the Turing machine. He was trying to develop a universal knowledge system with much greater elegance, structure and stability than the Web. So far as the development of the Web was concerned, Tim Berners-Lee did not apparently know about Nelson's work when he did his work, although he was probably familiar with HyperCard (created by Bill Atkinson), a product that used ideas from Nelson. Xanadu claims some credit for influencing a number of other products, such as Microcosm, Hyperwave, the Imedia system, and Crit. Nelson also thinks that the development of Andreessen's Mosaic were influenced by his work, although his view of browsers is that they are very silly since they are a window for looking at a large parallel structure, which is not shown in a useful way. Nelson says that his work was intended to stop something like HTML (and especially XML), because of its deficiencies, but he sees a role for HTML to be an output format , like Postscript. He remarks that trying to fix HTML is like trying to graft arms and legs onto a hamburger. The development model for Xanadu was the very opposite of that for Linux. There are many trade secrets, some of which are only being disclosed this week after Nelson announced at the O'Reilly Open Source convention that the Xanadu technologies were being put into the public domain. Work on the Xanadu idea started around 1960 and proceeded erratically with help from a changing handful of loyal first-generation hackers, mostly based in San Jose, but latterly with collaborators in Southampton, Japan and Australia. The Xanadu team invented its own terminology which to the uninitiated sounds in some ways like 18th century rifle drill. Nelson was ahead of his time, since there were no adequate object platforms in the early stages of his work. The use of ParcPlace Smalltalk was problematical because of the runtime fee. The Xanadu code - at least 300,000 lines in C++ or Smalltalk - mostly dates from the late 1980s and early 1990s. Whether it will provide anything of value today is hard to say. Nelson is very critical of software designers for their simplistic models which result in it being impossible to retrofit anything better. He points to the failure of the Web to be able to deal with two-way links, the problem of version management, and link management. However, the Web "has taken the niche that the Xanadu project was aiming for," Nelson says. Hypertext publishing as implemented on the Web, compared with the Xanadu visualisation, is like a conversation where two people are talking about "moving into space", but one means moving into a new office and the other means the colonisation of the solar system. Nelson describes himself as a contrarian, and he certainly has interesting if idealistic ideas. The lasting benefits of his work are his encouragement to consider what are now seen as alternative approaches, but which when his ideas were developed were innovative. Nelson's lifestyle and tangential views have provided plenty of good copy over the years. He delights in inventing terms like "cybercrud" [putting things over on people using computers], and is a fruitful source of one-liners: "No-one's life has yet been simplified by a computer. "In 1974, computers were oppressive devices in far-off airconditioned places. Now you can be oppressed in your own living room. "Bell Labs created Microsoft by charging $25,000 for Unix. If they'd charged $50, Unix would be the world standard. "What are video games so much better designed than office software? Because people who design video games love to play video games. People who design office software look forward to doing something else at the weekend." Nelson brings some refreshing views to such mundane things to metaphors like clipboards, which he observes you can't see; hold only one object; and whatever you put there destroys the previous contents. Most of Nelson's work has been devoted to what he calls a parallel universe, where documents are not independent, but have relationships that are not shown explicitly. The work has practical value in dealing with version control, which is only primitively handled by existing commercial software. Issues concerned with copyright, publishing and micropayments for authors have been overtaken by events like the open source movement, of which Nelson approves. For the new generation of hackers interested in knowing how the original hackers worked, there is no better introduction than a June 1995 Wired feature by Gary Wolf entitled "The curse of Xanadu". Nelson's present concern appears to be to get intellectual credit for his work, and putting it in the public domain is more likely to bring this about than the excessive secrecy that previously existed. The Udanax.com code is now being released for developers, but the server code, called Udanax Gold, is at present unusable "by those who haven't lived through its history" so is not being released at present. Perhaps one day there will be something better than the Web, and if there is, Nelson's ideas may well play a significant role. Register believe it or not factoid: Nelson's book Computer Lib was at one point published by Microsoft Press. Oh yes. ®
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