Derived from Jamie Blustein's alt.hypertext FAQ . The text may have been extended, edited, and modified for this Wiki; what is good is Blustein's and what is bad might best be attributed to a later hand.
It seems impractical to list all of the myriad of hypertext/hypermedia systems available today. I list some major systems (namely HyperWave/Hyper-G, Microcosm, Storyspace, Webthing, World Wide Web, and Xanadu) below. If you feel that some other system has been unfairly excluded then please write to me. If the list grows too long then it might become a separate posting or removed altogether. Also read about XML, SMIL and HyTime.
A family of SpatialHypertext tools, intended to help people create linear documents (research papers, films) through Amplified Representational Talkback. For MacOS and Windows.
An early hypertext tool by Peter J. Brown (University of Kent), Guide differed from familiar hypertext tools in adopting stretch text. Instead of link traversal leading the reader to a new window, links often replaced the link text with additional text. The underlying idea of stretch text has undergone a recent revival in the Fluid Hypertext work of Polle Zellweger and colleagues (LinkMe)
Originally released in 1987, Apple's HyperCard long inspired intense debate over the extent of its hypertextuality. HyperCard could be used for many things, and was difficult to use as a hypertext system. But hypertexts were written with HyperCard , and its role in the development of thinking about hypermedia cannot be denied.
HyperWave is a sophisticated Web document management system for large information spaces. The project began under the name Hyper-G in 1990. Among other things, it features hierarchical structuring, link management, attribute and full text search, access control, and interactive link and document editing.
An open and extensible hypermedia system designed for managing and disseminating unstructured digitally encoded files.
Described as a `writing environment designed for the process of writing. Storyspace is especially well suited to working with large, complex, and challenging hypertexts.' According to Mark Bernstein, its most distinctive features are its hierarchical backbone structure and dynamically flexible links with `guard fields', i.e. conditional links (links that are available only if certain nodes have been visited.
A SpatialHypertext system designed for making, analyzing and weblogging notes.
Webthing's holistic hypertext is an object-oriented hypertext system designed for collaborative authoring and implemented on the WWW (see below). Documents in Webthing generate HTML links from other documents on-the-fly, relieving authors of the need to manage HTML links, and eliminating the problem of outdated or uncoordinated references.
Note: This system will be unavailable for an unspecified time. For more information send e-mail to mailto:email@example.com or see the Webthing, Ltd. website.
See also:A search for WWW-based wikis will likely turn up systems with related functionality. A search for the term "open hypermedia sytem" will likely turn up more systems and architectures.
A SpatialHypertext system, developed by Cathy Marshall and Frank Shipman through the mid 1990's. Of great historical importance, VIKI generated several classic papers and has had broad influence despite its narrow usage.
VKB (Visual Knowledge Builder) 
A SpatialHypertext system, developed by Frank Shipman and colleagues at Texas A+M. Descendant of VIKI. Download for Macintosh or Windows
World Wide Web 
A very popular link-based hypertext system based on a client-server architecture running on the Internet.
-- Last edited October 27, 2002
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