Hypermedia Fundamentals

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					            Hypertext Research
                Lecture 1

                      Hugh Davis
                     All Notes on

                               6 lectures
    The Pioneers and 1st Generation Hypertext
    2nd Generation Systems, 7 Issues for the Next
     Generation Systems, and the Web;
    OHS and Microcosm
    OHS on the Web: Webcosm
    Link Integrity
    XML Linking
        – The Course will be supported by a reading list
        – Students should read all the papers; attending the lectures will get you
          the inside track from one of the key players

     Some key questions you should
       ask yourself as you study:
    What is hypertext? Nodes and Links with blue stuff to click on?
    What application areas has hypertext been applied to?
    What is open hypertext, and why did it only really develop in the
     research community?
    Is the World Wide Web open hypertext?
    Why has the World Wide Web been such a success?
    To what extent has the vision of the original pioneers been
    What are the pro's and con's of separating structure from content,
     and how does this apply on the web?
    What are the best tools for the job? (what job?)
    What is the future for hypertext?
    What are the outstanding research issues?

               The Pioneers: Bush 1
    As We May Think. Atlalntic Monthly 1945
     “The difficulty seems to be, not so much that we publish unduly in
     view of the extent and variety of present-day interests, but rather
     that publication has been extended far beyond our present ability
     to make real use of the record”
  Bush tackled this problem in terms of current
   technology - Microfilm and Photocells and
   typewriters (and voice recognition?!)
  On Microfilm: “Compression is important, however, when it
     comes to costs. The material for the microfilm Britannica would
     cost a nickel, and it could be mailed anywhere for a cent”

                The Pioneers: Bush 2
 “The real heart of the matter of selection, however, goes deeper than a lag in
    the adoption of mechanisms by libraries, or a lack of development of
    devices for their use. Our ineptitude in getting at the record is largely
    caused by the artificiality of systems of indexing. When data of any sort
    are placed in storage, they are filed alphabetically or numerically, and
    information is found (when it is) by tracing it down from subclass to
    subclass. It can be in only one place, unless duplicates are used; one has to
    have rules as to which path will locate it, and the rules are cumbersome.
    Having found one item, moreover, one has to emerge from the system and
    re-enter on a new path.
 The human mind does not work that way. It 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. It has other characteristics, of course;
    trails that are not frequently followed are prone to fade, items are not
    fully permanent, memory is transitory. Yet the speed of action, the
    intricacy of trails, the detail of mental pictures, is awe-inspiring beyond all
    else in nature.”

              The Pioneers: Bush 3
 A memex is a device in which an individual stores all his books, records,
    and communications, and which is mechanized so that it may be
    consulted with exceeding speed and flexibility. It is an enlarged
    intimate supplement to his memory.
 It consists of a desk, and while it can presumably be operated from a
    distance, it is primarily the piece of furniture at which he works.
    On the top are slanting translucent screens, on which material can
    be projected for convenient reading. There is a keyboard, and sets
    of buttons and levers. Otherwise it looks like an ordinary desk.
 In one end is the stored material. The matter of bulk is well taken
    care of by improved microfilm. Only a small part of the interior of
    the memex is devoted to storage, the rest to mechanism. Yet if the
    user inserted 5000 pages of material a day it would take him
    hundreds of years to fill the repository, so he can be profligate and
    enter material freely.

            The Pioneers: Engelbart 1
  a new stage of human evolution, characterized
   by "automated external symbol manipulation”
  augmentation of Man's Intellect
  1968 saw the realisation of NLS
        – “placing in computer store all of our specifications, plans,
          designs, programs, documentation, reports, memos, bibliography
          and reference notes, etc., and doing all of our scratch work,
          planning, designing, debugging, etc., and a good deal of our
          intercommunication, via the consoles”.
        – These consoles were very sophisticated by the
          standards of the day, and included television images
          and a variety of input devices, including one of
          Engelbart's best known inventions, the mouse
           The Pioneers: Engelbart 2
  Files in NLS were structured into a hierarchy of
   segments called "statements”
  Any number of reference links could be established
   between statements within and between files
    NLS provided viewing filters for the file structure:
        – clip the level (depth) of hierarchy displayed
        – truncate the number of items displayed at any level
        – write customized filters (in a "high-level content analysis
    NLS also introduced the concept of multiperson
     distributed conferencing/editing.

           The Pioneers: Engelbart 3
    NLS evolved to NLS/Augment marketed as a commercial
     network system by McDonnell-Douglas.
    emphasis on creating a consistent environment for
     "knowledge workers”
    The system included
        – many forms of computer-supported communication,
            asynchronous (e.g. email with links to all documents,
             journaling of ideas and exchanges, bulletin boards)
            synchronous (e.g. several terminals sharing the same display,

        – facilities for document production and control,
        – organisational and project information management (e.g. a
          shared calendar subsystem),
        – software engineering.

               The Pioneers: Nelson 1
        Since 1960, we have fought for a world of deep electronic
          documents-- with side-by-side intercomparison and frictionless
          re-use of copyrighted material.
        We have an exact and simple structure. Our model handles
         automatic version management and rights management through
         deep connection.
        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.

          The Pioneers: Nelson 2
    Intercomparison of parallel documents
    World-wide anarchic publishing
    Links that don't break
    Versioning
    Transclusion
    Transpublishing-- a new copyright zone

             The Pioneers: Nelson 3
    two types of connection
        – profuse and unbreakable *deep links* to embody the
          arbitrary connections that may be made by many
          authors throughout the world (content links);
        – a system of visible, principled re-use, showing the
          origins and context of quotations, excerpts and
          anthologized materials, and content transiting
          between versions (transclusions).

            The Pioneers: Nelson 4
    Transclusion is what quotation, copying and cross-referencing
     merely attempt:
    they are ways that people have had to *imitate* transclusion, which
     is the true abstract relationship that paper cannot show.
    Transclusions are not copies and they are not instances, but *the
     same thing knowably and visibly in more than once place*.
    While copies and cross-reference are workarounds in place of
     transclusion, aliases and caches are *forms* of transclusion.
    Not distinguishing between links and transclusions is causing misery
     everywhere, for instance in lawsuits against having one's page
     brought into someone else's frame (a form of transclusion) which
     the lawyers refer to as "linking"-- hopelessly confounding a key
    Note also that the famous "trails" of Vannevar Bush's memex
     system were to be built from transclusions, not links
                          1987 - Conklin
    In 1987 Conklin produced “A Survey of Hypertext”
    This article attempted for the first time to define the
     scope of this area of computing.
        – The concept of hypertext is quite simple: windows on the
          screen are associated with objects in a data base and links are
          provided between these objects, both graphically (i.e. as
          labelled icons) and in the data base (i.e. as pointers). [....] So
          what is all the fuss about? Why are some people willing to
          make such extravagant claims about "idea processing" and "a
          basis for global scientific literature"?
        – there is growing interest in the extension of hypertext to the more
          general concept of hypermedia , in which the elements which are
          networked together can be text, graphics, digitized speech, audio
          recordings, pictures, animation, film clips, and presumably tastes,
          odors, and tactile sensations. At this point little has been done to
          explore the design and engineering issues of these additional modalities
           Conklin 1: Macro Literary
    the study of technologies to support large on-
     line libraries in which inter-document links are
     machine supported – all publishing, reading,
     collaboration, and criticism takes place within
     the network;
        – e.g. Memex
        – e.g. NLS/Augment
        – e.g. Nelson's Xanadu (?)

        – Now the Web would fit in this area

     Conklin 2: problem exploration
    tools to support early unstructured thinking on a
     problem, in which many disconnected ideas come
     to mind, such as early authoring and outlining
     ("idea processors"), problem solving, and
     programming and design;
        – e.g. Goldstein and Bobrow's PIE 1980. Software
          Development had contexts and layers
        – e.g. Issue Based Information Systems (IBIS (73), g-
          IBIS (86)) - had typed links
        – e.g. UNC's Writing Environemnet (WE)(86) allows
          construction of linear text from network of nodes

        Conklin 3: browsing systems
    similar to macro literary systems, but smaller
     scale – systems for teaching, reference, and
     public information, where speed of access and
     ease of use is crucial;
        – e.g. CMU's ZOG (84) and Knowledge Systems' KMS
          (next, back and menu of cross-ref links)
        – e.g. Shneiderman's Hyperties (86) Ran under DOS
        – e.g. Symbolics Document Examiner (85) A
          sophisticated programmable Help System

        Conklin 4: general hypertext
    general purpose systems designed to allow
     experimentation with a range of hypertext applications –
     most commonly applied to reading, writing, collaboration
        – e.g. Xerox PARC's NoteCards (87) Intended to help information
            analysts build conceptual models. Benefited from Xerox Model D
            screens and use of Lisp interface for extensibility
        –   e.g. Brown University's Intermedia (85). A framework with a
            collection of tools. Allowed more than one Web of links.
            Educational purpose.
        –   e.g. Tektronix Neptune (1986) based on HAM. Versioning was a
            major feature. Used for CAD.
        –   e.g. Guide from OWL (1986) Used Apple Mac and Windows 2.0 A
            folding editor metaphor
        –   e.g. Hypercard. (1987) A Stack of Cards metaphor. Appletalk
            object and event based programming language.
             Conklin: The Essence of
                   Hypertext 1
    Nodes
        – The power to chunk information
    Links
        – importance of speed of link resolution
        – direction?
        – Names?
        – properties?
        – How many ends?
        – End as region or node?
        – Reference by name or by value
        – display characteristics?
          Conklin: The Essence of
               Hypertext 2
    Trees (strict hierarchies) or networks of links
    Clusters of Links (webs/linkbases?)
    Clusters of Nodes (Composites)
    History
    Trails
    Authoring and Annotating!
    Browsers (meaning node level)

        Conklin: disadvantages of
    disorientation: the tendency to lose one's sense
     of location and direction in a non-linear
     document; “Lost in Hyperspace”
    cognitive overhead: the additional effort and
     concentration necessary to maintain several
     tasks or trails at one time.


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