Spatial hypertext: An alternative to navigational and semantic links

{{Summary
 * title=Spatial hypertext: an alternative to navigational and semantic links
 * authors=Frank M. Shipman III, Catherine C. Marshall
 * tags=hypertext, spatial hypertext, review papers,
 * summary=This paper reviews the history of spatial hypertext, from its pre-history (Bush, Robertson, Engelhart), to the problem motivating their creation (reader confusion/disorientation in large hypertexts). The first spatial hypertext systems date from 1987-1991: NoteCards (see NoteCards in a nutshell), gIBIS (see gIBIS: A hypertext tool for exploratory policy discussion), and Aquanet (Aquanet: A hypertext tool to hold your knowledge in place).

It is extensively referenced--2 of its 5 pages are references--and functions as a review paper providing historical perspective.

Observations about Spatial Hypertext
Relationships between nodes could be shown in more than one way: beyond directed links, there is also node proximity (spatial) and visual attributes. New interface needs emerged, included supporting the "implicit and transient" relationships between nodes, which engendered a need to support manipulation, and add visual attributes of nodes that could quickly be changed, as well as further structure such as stacks and lists of nodes.

Benefits of Spatial Hypertext

 * 1) uses people's visual memory and pattern recognition
 * 2) facilitates "constructive ambiguity" - "placement of a node close but not quite with others can imply some indecision or potential for a relation between the nodes." This is helpful for tasks "where interpretations form" along the way, during the task, such as analysis and design.
 * 3) supports emerging problem-solving strategies - visual language changes over time as the task unfolds - meaning that predefined types and relations are unhelpful (there's too much overhead in changing them)
 * 4) reduces communication overheads - "In contrast with a navigational hypertext or file system, effective use of ambiguous and implicit relationships means the spatial hypertext does not require on users to agree on particular relationships or agree on their interpretation."

Impact of Spatial Hypertext
This section discusses the impact of spatial hypertext. It reviews theoretical discussions of hypertext where spatial hypertext has played a role; cites advances in visualization of hypertext networks (e.g. algorithms automating visualizations, 3D representations, fisheye views); discusses research challenges such as converting between document-centered and spatial hypertext models, and reviews "Web workspaces". }}
 * journal=ACM Computing Surveys
 * pub_date=1999
 * doi=10.1145/345966.346001
 * subject=Computer Science
 * journal_vol=31
 * pub_open_access=spatial hypertext, hypertext