5d. Xanadu and the Web

Ted Nelson

The final step that we need to discuss in this lecture is the next hypertext vision: Xanadu. Xanadu presented an idea of a computer filing system that would store and deliver all of the world's literature through hyperlinked text, while acknowleging authorship, ownership, and quotations. It would be like the World Wide Web that you understand today, but with no broken links, no lost documents, and a micropayment system built right into its core.

To understand Xanadu, we need to briefly understand its inventor: Theodor Holm Nelson, better known as Ted Nelson. Similar to Bush and Engelbart, Nelson had a theory around how human knowledge was both inherited and transmitted.

Ted Nelson, unlike Bush and Engelbart, came at this problem a bit differently. If we think of the University of Waterloo, Bush and Engelbart would be coming from the north side of campus (Engineering, Computer Science) – whereas Nelson would be coming from the Faculty of Arts from the south side! (Go Porcellino)

Nelson is a graduate student at Harvard University in 1960, studying sociology. He is having trouble keeping his notes clear and tries many methods. Many of these might be familiar to you as an undergraduate student – file cards, index tabbing, edge-notched cards. Making multiple copies of documents and then copying them multiple times to mash them up. You can imagine. None of these methods seemed to solve the major problem Nelson now saw himself as being confronted with: the need to have information in several places at one time.

Image of Ted Nelson.
 
Image of edge-notched card, file cards and index tabbing.
 

What to do?

Fortunately, for the development of hypertext, Nelson then takes a computer course. He then begins to think about how computers could be put into the service of information handling.

Hypertext Defined

The first major idea that gives rise to hypertext is Nelson’s “Evolutionary List File” or ELF. In a nutshell, ELF allows a user to compare documents. Crucially, it helps him get published in the ACM 20th National Conference. This gets hypertext to appear in print.

It is worth us looking at this paper in a bit more depth. Please read the first three paragraphs below.

This 1965 paper on “A File Structure for the Complex, The Changing and the Indeterminate” outlines the approach to this new idea of Hypertext.  The first excerpt, below, notes how the costs of computing are now down considerably by 1965, which I think really helps both understand why he thinks computers are exciting – but also it’s worth a bit of a chuckle to see how expensive computing is at that time. Crucially, after introducing Vannevar Bush and citing the Memex a few times, we come to the pivotal passage in the paper:

Read the above passage in depth, as it provides the definition of hypertext that both inform this lecture but crucially the lectures that follow.

Crucially, we see the idea of the link here. Both Engelbart and Nelson independently invent the concept of a link. But in this case, Nelson’s link is also a bit different – its links are bidirectional. Indeed, today, Nelson will still call the World Wide Web a series of “one-way hyperlinks”. Out of this idea would come some of the kernels for today’s World Wide Web.

Xanadu

But before we get to the World Wide Web, both in passing at the end of this module and then in more depth in future modules, we should discuss Nelson’s implementation of Hypertext: Xanadu.

 

Pause and Reflect: Xanadu

To understand Xanadu, read The Xanadu Parallel Universe. In particular, pay attention to the following:

  1. How does Xanadu work?
  2. How is it similar to the World Wide Web that you use today?
  3. How is it different from the World Wide Web that you use today?

Note: This is for individual reflection only; you are not required to submit your answers.

You may be curious, as you have never used Xanadu before. What happened to it? Why was it never realized? The actual history of Xanadu is a bit outside of the scope of this class. In 1995, Wired magazine wrote a famous article “The Curse of Xanadu", describing it as the “longest-running vaporware project in the history of computing”.

Xanadu continues under active development today, as we can see in this demonstration from Ted Nelson himself.

 
 

While Xanadu’s dream continues on, the Web will ultimately become the dominant and most-widespread version of Hypertext. 

Conclusions and Next Steps

In this module, I have only provided a few examples of hypertext. At Wikipedia, there is a well-maintained list of other forms of Hypertext implementations – if you are curious, please feel free to check it out.

The next logical step for us in this course, will be the World Wide Web. In the “Birth of the Web” module, we will explore the link between these earlier hypertext modules and the Web. In a nutshell, Tim Berners-Lee would develop the World Wide Web while he was a physicist at the European Organization for Nuclear Research or CERN in Geneva, Switzerland. Berners-Lee will find himself in a complex, ever-changing environment of people coming and going, and will begin to create ideas of bringing order to chaos in 1980.

Through this module, however, hopefully you can see that the history of the Web cannot be seen as just beginning with Tim Berners-Lee and his specific implementation of hypertext in 1989. It comes from a rich heritage dating back Vannevar Bush and his 1945 “As We May Think”; Douglas Engelbart and the oN-Line System (NLS); and Ted Nelson and Project Xanadu.

This week we have covered a lot of ground. As noted at the beginning of the module, we had the following three goals which have been achieved in three different ways:

  • Have a conceptual understanding of hypertext and its history: We explored this through the beginning idea of hypertext with Vannevar Bush and the Memex; its implementation in the NLS under Douglas Engelbart; and the definition of the term itself and early visions of interconnected documents in Project Xanadu.
  • Compare and analyze historical hypertext systems to contextualize today’s World Wide Web: We were able to see the differences between Memex, NLS, and Xanadu – both which each other, and crucially, from the Web that you all use today.
  • Understand three pivotal moments in the development of hypertext through close document readings: We have read something close from each. Bush’s “As We May Think”,  “Mother of All Demos” and NLS; and explorations of Ted Nelson’s pivotal 1965 ACM paper.

Bibliography

Text

Nelson, T. H. “Complex information processing: a file structure for the complex, the changing and the indeterminate,” ACM ’65: Proceedings of the 1965 20th National Conference, https://dl.acm.org/citation.cfm?id=806036. 

Media

Gotanero. "Ted Nelson (November 2013)". Wikimedia Commons. November 2013. https://commons.wikimedia.org/wiki/File:Ted_Nelson_(November_2013).jpg (accessed December 12, 2019), licensed under CC BY 3.0

MacKay, Daniel. Edge-notched card. Edited by Wikipedia. March 26, 2008. https://en.wikipedia.org/wiki/File:Edge-notched_card.jpg (accessed December 13, 2019).

 Module 5 is complete! Please return to the Table of Contents.