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II. From HyperCard to the World-Wide Web (1994)

1. The Coming of the Web

Undoubtedly, the single-most important event in terms of the Internet during the 1990s was the development and impact of the World-Wide Web. With the widespread distribution of NCSA's graphical browser Mosaic, followed up by the even more popular Netscape, the use of the WWW has grown dramatically (some estimates claim that traffic on the WWW increased by c.1,000% in 1993 and c.400,000% in 1994). Coupled with this, the background mark-up language HTML (Hypertext Mark-up Language) is so relatively easy to use that this has enabled many people (with limited programming knowledge) to easily mount publications on the Internet. Although recent SIMA reports have provided excellent introductory material on the WWW (see Kelly, 1995) the following may act as a general guide to the Web.

1.1 How the World-Wide Web Works

The World-Wide Web is a system whereby machines around the world store their documents in a standard form. These documents consist of text but can be linked to graphics, sound files, movies, and to other documents simulating a hypertext environment. The revolutionary attribute of the World-Wide Web is that the linking of these documents can be international as long as the address of the document to be linked to is known. In addition, the WWW can interface with other accessing systems such as Gopher sites.

WWW documents are stored as plain text files (i.e. ASCII) and are marked up using a system called the Hypertext Mark-Up Language or HTML (a subset of the Standard Generalised Mark-Up Language--SGML). These documents then reside on a machine that acts as a server. To access these documents (and make any sense of them) one needs a WWW browser. Common browsers used at the moment are Netscape, Mosaic, and LYNX (for use as a plain text browser on a terminal); but there are many others already available or under development.

When browsing a document on the Web you will need to know its Uniform Resource Locator or URL. Though daunting to look at these simply record the scheme or protocol of the document and its pathname (i.e. the location of the document itself). One of the major advantages of the Web is that it can interface with several systems such as Gopher, FTP, or WAIS, thus allowing it to tap into previous Internet resources with ease. Documents produced for the Web and marked-up in HTML use the hypertext transfer protocol or `http'. For example, the URL for the Times Higher Education Supplement is:

http://www.timeshigher.newsint.co.uk/

Here the prefix `http' denotes that it is marked-up in HTML for the Web, and `www.timeshigher.newsint.co.uk' is the pathname or Internet address of the document.

Within the Web documents themselves, links can be made to images (so that they appear as part of the file when reformatted by the browser), other documents (including remote access to sites elsewhere), sound files, and video files. Interactive graphics can be displayed with links attached to a number of elements; users need only click on the relevant section to activate them (e.g. see the interactive maps at Xerox -- http://pubweb.parc.xerox.com/map). With the presence of links, graphics, sound, and video, the Web is clearly the first step towards providing multimedia on an international basis.

2. Abandoning HyperCard

At the end of the last chapter it was noted that development of Rosenberg 2.0 never reached completion. This was due to the fact that HyperCard was deemed no longer adequate and that no other multimedia authoring tool offered a suitable alternative. The decision then, was taken to move away from traditional authoring packages to mount the next version of the Rosenberg material on the World-Wide Web. This decision, however, needs further clarification.

The choice for a multimedia author at the moment is coming down to two options. First, one can proceed with the standard authoring packages such as HyperCard, SuperCard, ToolBook, Director, and so on. Second, one can consider moving the publication onto the Internet via the very popular medium of the World-Wide Web. As can be seen from the above opening remarks the decision was taken to move the Rosenberg material onto the latter after much deliberation over the merits of each delivery medium. In an effort to help other developers in their project decisions some of the advantages and disadvantages of each have been listed:

3. Multimedia Authoring Tools (e.g. HyperCard, ToolBook, Director)

3.1 Advantages

  1. Most of them have very sophisticated editing tools and functions allowing for elaborate special effects, screen design, inclusion of multimedia elements, and linking between applications. Background scripting languages can also allow for the addition of advanced functions.
  2. Most will allow run-time versions to be distributed without the need for third parties to have the full version of the software they were created in (e.g. HyperCard player, etc.).
  3. Due to their long history of development there is a substantial amount of supporting material and publications to help a prospective author.
  4. The author tends to have control over the data, restricting its distribution, as well as the end-users' abilities to alter material.

3.2 Disadvantages

  1. Every authoring package has its limitations. For example, HyperCard is poor in using colour, ToolBook (like HyperCard) is limited to a single platform, Director is poor in handling hypertext, and so on. Although these may be overcome in the future the situation at present is far from desirable.
  2. Unless the author creates specialised importing features most of the data used in the final product will be locked into the package making subsequent editing a problem.
  3. The life-expectancy of these products is questionable. Who is to say that a program designed in HyperCard will be usable in two or three years time with the speed at which new machines and operating systems are emerging?
  4. The potential audience is limited by the distribution process (e.g. cost and speed of producing CD-ROMs), and the platform requirements. Mounting compressed programs on the Internet for FTP will also dictate a limitation on the size of the product.
  5. If the product is upgraded this would have to be in conjunction with a re-issue of a new version, entailing all the problems of advertising these changes, plus a renewed round of distribution.
  6. Although software houses have made great strides in making the authoring software more easy to use it should still be noted that the learning curve for some products is still very high.

4. The World-Wide Web

4.1 Advantages

  1. Assuming one has access to a Web server (usually your institution's mainframe), publication of material (not including copyright costs) is free.
  2. HTML, the hypertext mark-up language used in creating World-Wide Web documents, is very easy to learn.
  3. The Web uses non-propriety standards thus giving the site a longer life expectancy: e.g. text is in plain ASCII, HTML is a sub-set of SGML, graphics appear as JPEG or GIF (thus industry standard), etc. It is subsequently cross-platform (i.e. the same document can be viewed through a Macintosh, a Windows machine, a UNIX box, and even a dumb terminal using such browsers as LYNX though this necessitates the loss of multimedia elements).
  4. Once established, the material is made available to an international audience amounting to millions (with no extra distribution costs).
  5. Linking from the document is not restricted to data elsewhere on the machine's hard drive or the CD-ROM the program is distributed on, but can be international (e.g. if a new site appeared giving historical information on the First World War a link could be created to this within a matter of minutes).
  6. At present the browsing software needed for the Web is free (e.g. Netscape or Mosaic) and this has led to its enormous popularity.
  7. The Web can deliver multimedia elements in addition to text (although only graphics were employed in this site).
  8. Editing of existing files is straightforward. Furthermore, as it works on a client/server basis there is no onus on the developer to reissue upgrades.
  9. There are substantial moves in developing the Web. Already it can easily launch other applications, interrogate databases, etc. Any limitations at the moment could well be overcome in the very near future with advances in CGI scripting.

4.2 Disadvantages

  1. At present, the screen design facilities and animation capabilities of the Web are not as advanced as those provided with most of the authoring packages. However, Macromedia's Shockwave (a href="http://www.macromedia.com">http://www.macromedia.com) goes someway to addressing this allowing movies created in the authoring package Director to be played by Web browsers, and to have interactive links embedded within them. Similarly, the community is placing a lot of expectations on the benefits it is hoped Sun Microsystem's programming language Java will bring to Web development (http://java.sun.com).
  2. Access on networks is slow (probably the most consistent criticism levelled at publishing on the Internet). Although this may improve with time this is a serious problem that will continue to frustrate on-line teachers and publishers. However, in answer to this, it should not be forgotten that HTML files can be read from local networks or hard drives thus dispensing with the reliance on the speed of the Internet. Academics wishing to provide on-line tutorials or notes via the Web could even distribute their files on floppy disks.
  3. By opening up access to an international audience there are serious implications for copyright issues. A developer wishing to publish on the Web will probably have to agree world rights on the material they use.
  4. As well as often being limited to a document metaphor (e.g. Web documents are designed more or less to be read from the top scrolling down to the bottom), overuse of inlaid graphics can greatly impede the downloading of material. This is the major problem with many Web sites around which use meaningless graphics simply for decorative purposes. This site attempted to avoid this by placing the emphasis on quantity rather than artistic value.

Although the above is a very simplified list of points both for and against the different delivery platforms, it does give some indication as to why the medium of the Web was chosen. The ability to easily edit material, deliver it to an international audience quickly, cheaply, and cross-platform, and to keep the data free of propriety software all added up to make the Web the most attractive prospect.

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