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DILLON, Andrew

Hypertext in Context [1]

Simply stated, hypertext consists of nodes (or 'chunks') of information and links between them. Stated thus, it is easy to find early examples of hypertext any text which references another can be seen as two nodes of information with the reference forming the link; any text which uses footnotes can be seen as containing nodes of information (the text and the footnote), with the footnote marker providing the link or pointer form one node to the other. As we shall see later, the idea of a node is very general, and there are no 'rules' about how big a node should be or what it should contain. Similarly, there are no rules governing what gets linked to what. What makes hypertext different, what sets it apart from the most conceptually inter-linked paper document, is that in hypertext the links are 'machine-supported'. When the reader selects a hypertext link, the 'movement' between the two nodes takes place automatically. It is for this reason that the advent of hypertext has had to wait for the combination of processing power and display embodied in the modern computer. [...] A node of information can be a fragment of music, a piece of text, a map, a complete film anything which the author thinks can sensibly be presented as a unit. Even if a particular hypertext system always displays one screenful of information at a time, a node can consist of several consecutive screens. Similarly, a link is arbitrary in the sense that there are no rules to say where a link shall be made. A link can be made between any two nodes which the author (or often the 'reader' as we shall see later) considers to be connected in some way. In some systems, the links are 'typed', i.e., there are several types of link and the author must specify which type he would like to make at any one time. For example, the system might limit links to those which connect information offering support for an argument, refutation of an argument, an example and so forth. However, many systems use untyped links.

MCKNIGHT, Cliff et Andrew Dillon Hypertext in Context, Cambridge, Angleterre, Cambridge University Press, 1991, 166 pages.

Hypertext historical highlights Rather than indulge in historical oneupmanship who knows, maybe the scratchings around the cave paintings were the first primitive hypertext links? we will begin our brief overview of the history of hypertext in the same era as the birth of the technology which supports it. The article most often cited as the birthplace of hypertext is Vannevar Bush's "As we may think" (Bush, 1945). [...] Bush was appointed the first director of America's Office of Scientific Research and Development by President Roosevelt in 1941. He saw clearly the problems associated with ever-increasing volumes of information: "There is a growing mountain of research. But there is increased evidence that we are being bogged down today as specialization extends. The investigator is staggered by the findings and conclusions of thousands of other workers conclusions which he cannot find time to grasp, much less to remember, as they appear. Yet specialization becomes increasingly necessary for progress, and the effort to bridge between disciplines is correspondingly superficial." Presented with an extract such as this, it surprises many people to discover that the author was writing 45 years ago, since many contemporary writers have made exactly the same point about the 'information explosion'. To cope with this plethora of information, Bush designed (conceptually, at least) the 'memex', a device "in which an individual stores his books, records, and communications, and which is mechanized so that it may be consulted with exceeding speed and flexibility." More than a simple repository, the memex was based on "associative indexing, the basic idea of which is a provision whereby any item may be caused at will to select immediately and automatically another. This is the essential feature of the memex. The process of tying two items together is the important thing." For Bush, 'tying two items together' was important because it seemed to him to follow the workings of the mind, which "...operates by association. With one item in its grasp, it snaps instantly to the next that is suggested by the association of thoughts, in accordance with some intricate web of trails carried by the cells of the brain." In view of the way we described the essential features of hypertext earlier, it is not difficult to see why Bush is often regarded as its founding father. In conception, the memex was a remarkable 'scholar's workstation' and Bush thought that it would allow a new form of publishing, with documents "ready-made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified." Unfortunately for a visionary like Bush, the technology of the day was not up to the task of instantiating the memex. He assumed that microfilm would cope with the bulk of the storage problem, which might have been true. However, the level and complexity of indexing and retrieval required by the memex was certainly beyond microfilm-based technology. The memex was a problem in search of a solution, and the solution was the computer. The one thing which Bush did not do was to name this nascent field of endeavour. The term 'hypertext' is attributed to Theodor (Ted) Nelson, a character who 25 years after coining the term can still hold an audience's attention with his vision of how the future of literature might look. Nelson's Xanadu project characteristically named after the site of Kubla Khan's pleasure dome in Coleridge's poem is aimed at the creation of a 'docuverse', a structure in which the entire literature of the world is linked, a "universal instantaneous hypertext publishing network" (Nelson, 1988). In Xanadu, nothing ever needs to be written twice. A document is built up of original (or 'native') bytes and bytes which are 'inclusions' from other documents in which they are themselves native. By the Summer of 1989, Nelson had moved from speaking of 'inclusions' to speaking of 'transclusions', a term which implies the transfer and inclusion of part of one document into another. However, an important aspect of Xanadu is that the transclusion is virtual, with each document containing links to the original document rather than copies of its parts. It could be argued that someone who speaks of a docuverse, xanalogical structure and transclusions should not be surprised that his project is "not well understood". However, Nelson continues to work towards his vision, publishing details of the 'humber' system for keeping track of the large number of documents in the docuverse (Nelson, 1988) and distributing flysheets announcing the imminent availability of the Xanadu Hypermedia Information Server software. Although Nelson is seen as one of the gurus or Grand Old Men of hypertext, the idea of much of the world's literature being connected had been suggested many years previous. At a talk given in 1936 (and subsequently published in 1938), almost ten years before even Bush's article, the British writer and visionary H.G. Wells had described his idea of a World EncyclopŠdia, the organization of which would:..."spread like a nervous network...knitting all the intellectual workers of the world through a common interest and a common medium of expression into a more and more conscious co-operating unity." In a world which was about to be embroiled in the greatest war ever, Wells's article can be seen as a plea for thinking people to work together in peace. Modern political theorists might now judge the article to be na´ve, but the practicalities including issues like copyright which Wells foresaw are still being worked on today in the field of hypertext. Nelson may have given hypertext its name but he was by no means the only person working on the ideas. Although perhaps better known as the inventor of the mouse pointing device and the five-key 'chording' keyboard, Doug Engelbart has been pursuing his vision of hypertext since the early 1960s. Engelbart's emphasis has always been on augmenting or amplifying human intellect, a fact now reflected in the naming of his system as Augment. His original proposal was for a system he called H-LAM/T Human using Language, Artifacts and Methodology, in which he is Trained although the first implementation had the simpler title of NLS oN Line System. NLS was meant as an environment to serve the working needs of Engelbart's Augmented Human Intellect Research Centre at Stanford Research Institute, a computer-based environment containing all the documents, memos, notes, reports and so forth but also supporting planning, debugging and communication. As such, NLS can be seen as one of the earliest attempts to provide a hypertext environment in which computer-supported collaborative work could take place [...]. We can see Bush, Nelson and Engelbart as representing three different views of hypertext which continue to attract adherents today. The Bush view sees hypertext as somehow 'natural', reflecting the mind or (in the strongest form of this position) modeling the mind; from this perspective, hypertext should feel easy to use. The Engelbart view of hypertext is as an augmentation environment; the user of hypertext should be able to achieve more than would be possible without it. Although Nelson's vision is perhaps the most ambitious, his view of hypertext is as a storage and access mechanism; the user of hypertext should be able to access any document; and such ease of access should work to break down subject boundaries. These views are not mutually exclusive; it is possible to advocate a hypertext system which provides ready access to all information and therefore allows users to perform new tasks. Indeed, there is a fine line between these idealized positions and it is not always possible to describe any particular system (or system designer's viewpoint) in terms of one or any of them. However, the fact that different views can proliferate illustrates the point that 'hypertext' is not a unitary concept, not a single thing which can be defined any more precisely than in terms of nodes and links It is for this reason that hypertext software packages with completely different 'look and feel' can be produced and still claim to embody the concept of hypertext.

MCKNIGHT, Cliff et Andrew Dillon Hypertext in Context, Cambridge, Angleterre, Cambridge University Press, 1991, 166 pages.

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