11.1 Intermedia Web View

Intermedia is one of the most frequently cited research hypermedia systems [Yan88]. It was developed from 1985-1990 at the Institute for Research and Scholarship (IRIS) at Brown University and was used as a testbed for novel programming, hypertext and multimedia concepts. Using object oriented programming techniques, Intermedia offers a seamless integrated hypermedia information environment including integrated text editor, drawing editor, pixmap painting editor, timeline editor, animation editor, scripting environment and hypermedia mail system [Yan88], [Jac91]. Among other issues, the Intermedia team also addressed the problem of becoming disoriented and being lost in hyperspace. One of their main remedies was the automatic generation of an overview map of a hypermedia document. They implemented different versions of automatically generated overview maps, where the maps always reflected the actual linking structure. This means, that their maps were based on hardwired, static links made by a designated person. In the first version, all nodes and links of a hyperdocument were represented on the screen (figure I.50).

Figure I.50 Spider web view of Intermedia document (ExFig 10 from [Con87b])

Figure I.50 illustrates the problem of displaying all links and nodes of a document in a single view. Obviously this overview map becomes a meaningless tangle as soon as the number of nodes and/or links exceeds just a few. To overcome this problem, Utting and Yankelovich describe a refined overview map based on the Web View [Utt89]. They distinguish between local and global maps. The type of map displayed in figure I.50 is called a global map, because it shows all nodes and links in a document. A simpler global map is shown in figure I.51.

Figure I.51 Global map (ExFig 2 of [Utt89])

By only showing the local context of the actual node, the global map can be disentangled. But at the same time, the global context information is lost (figure I.52). This type of map is called a local map.

Figure I.52 Local map (ExFig 3 of [Utt89])

The Intermedia Web View combines a record of the user's path with a map of the currently available links. The web view consists of three components: the path, the map and the scope line (figure I.53).

Figure I.53 Intermedia Web View (ExFig 12 of [Utt89])

The path component of the Web View contains a catalog of the nodes the user has last visited. It is a simple sequential list similar to the UNIX history command. The Web View map is similar to the local map shown in figure I.52. Compared to the original layout in figure I.52, the icons have been reduced in size and are laid out in rows in alphabetical order. The Web View scope line displays the number of nodes and number of links in the web. It has thus inherited one of the functions of the global map by giving the user a feeling for the size and link complexity of the actual web.

By integrating concepts of local and global map into one unified view, the Intermedia Web View achieves a high functionality on limited space. The main drawback of the Web View is the fact that it is based on static links. This means, that the web view reflects the local context of a node based on the hardwired links connected to that node. There is no way for the inherent document structure to be reflected in the Web View. The Web View also offers no easy way of scaling for very large webs. The only place where the size of the web is reflected is in the scope line which tells the user the number of nodes and links in the web.

Nevertheless, the Intermedia Web View is an excellent example for a well thought out overview map. It integrates all the basic concepts and offers a convenient method of orientation and information retrieval in complex hypermedia documents.

The Intermedia Web View displays a static picture of a hyperdocument. The fish eye view concept described in the next section presents a personalized view of an information structure by permitting to define a focus of interest.