Collaborative hypertext

[whisper]

Collaborative hypertext

In his original proposal for an information system for CERN, Tim Berners-Lee said that it should:

'enable users to add their own private links to and from public information, and to annotate links as well as nodes privately, and enable 'live' links to be made between dynamically changing data.' (A Brief History, p.235).

In realizing this proposal, Berners-Lee invented an interface: a program which stood between the user and the vast and disparate information resources of the Net. In seeking a model for this interface he drew heavily on ideas which had emanated from the hypertext community, where the problem of navigating through a virtual space of linked texts had been addressed through the notion of a ' browser', i.e. a virtual window which displayed the structure of the space. The Xerox NoteCards system developed in the early 1980s, for example, had a special 'browser card' which displayed editable node-link diagrams showing the structure of some portion of the hypertext network currently in use. Other hypertext or hypermedia systems had similar tools. But to the original hypertext notion of browsing, the CERN people added something which echoed the thinking of Ted Nelson, namely the idea that documents should be editable by their readers. Berners-Lee's idea of a browser, therefore, was not just an interface that would provide passive viewing, but something that would allow users to create their own inline links even as they were reading a document. Unfortunately, this is the one part of his vision of the WWW which did not survive beyond the CERN version. However, while many people think of hypermedia only in terms of the WWW, hypertext research has in fact been going on since the early 1960s, when Englebart developed NLS. Since then researchers have been developing a wealth of features and theories focusing on structuring, presenting and accessing interrelated information.

Why is hypermedia seen as a good way to handle information, and why would people want to add their own annotations to hypertext documents or web pages? There are probably many answers to these questions but I'd like to explore two of them with you now.

Interactive learning
In the area of education it is well known that interacting with information rather than just passively reading it actually helps a learner to learn. That is why we have encouraged you to write your own notes on the material as you have been covering it in this course. At the simplest level, people often underline or highlight key words or sentences on printed documents, or they may scribble notes in the margin. Wouldn't it be great if you could simply add notes and highlights as you were browsing a page and they would always come up whenever you viewed that page again? The problem with this is that you don't have write access to the server on which the page is held, so you can't edit the pages and save information on them. It would be problematic if we allowed this for every student; you would get everyone else's notes as well as your own when you viewed the page, and the result would be a bit confusing to say the least. However, if a browser could be made to keep a record of your notes and where they fitted in relation to the page, but stored your notes with their associated links on your hard drive, then such a system could work. This process is called web augmentation, and researchers are looking at ways to make this possible using new versions of the existing browsers. You can read an interesting account of progress in this field in the PhD thesis of Niels Olof Bouvin: Augmenting the web through open hypermedia . (This is very readable but rather long; it is after all a thesis!) A pdf is available, which will take about 10-15 minutes to download using a 56k modem; you may wish to save it on your computer for later reading: Augmenting the web through open hypermedia.

Open hypermedia standards
Standardization is an issue in this area. As hypertext systems developed, producers invented their own ways of storing, accessing and presenting information. This led to the situation where different hypertext systems could not read each others' files. The goal of the Open Hypermedia Systems Working Group is the introduction of hypermedia technology into as many existing applications and computing environments as possible, to gradually evolve a world-wide unified hypermedia environment. To do this would require the development and adoption of open hypermedia standards and protocols that allow interoperability between different hypermedia applications.

Collaboration: the underlying ethos of the Web

There are several examples of people using the Web to work collaboratively, many of these in the arts and literature, and this offers a rich means of sharing and working creatively together.