Wikis are a most fascinating manifestation of web-based groupware.
"Wiki wiki" means "quick" in Hawai'ian. They call the shuttle at the Honolulu airport the wiki wiki bus.
Wikis were invented by Ward Cunningham, and are a way of allowing users to update web pages in a highly collaborative way:
Each page contains a tag that allows you to edit it. That way, if the information is incomplete, or there is something you feel worth adding/changing/fixing, you can.
Capitalized words are used to automatically generate an option of adding a page somewhere else on the Wiki to describe the capitalized item. As a result, a Wiki is an extremely natural way of constructing a glossary of terms and interlinking definitions thereof.
There are many WikiWikiClones
ZWiki - a Wiki implemented atop Zope.
Allows building objects that use Python / Zope capabilities to provide sophisticated dynamic behaviour.
CLiki - a Wiki implemented for and using Common Lisp.
MoshiMoshi Wiki - implemented in Scheme
This isn't a Wiki, but rather a somewhat Wiki-like project whereby some 20,000 editors are building index material on Internet resources.
A number of wiki implementations have emerged that use Section 1 as the data store
Wiki written in Haskell using Git as data store
Before "the web," there was Gopher. Gopher provides a rather simpler operating paradigm; where web folk have been struggling to turn HTML into a form rendering language and/or Desktop Publishing system, Gopher stays with the notion of having a clear hierarchy of Files (documents) and Directories (providing opportunity to jump to a new list of documents).
The "train wreck" of competing HTML standards that frankly continues would certainly go along with the "Gopherians" contention that they had something simpler and more useful. Gopher is not particularly well-suited to "e-commerce" applications, but most certainly is good for searching for information.
It would be criminal to not make mention of the overall originators of the concept of hypertext. It was certainly not the lawyers of Microsoft that invented the notion.
Vannevar Bush came up with the original concept of having a "crosslinking of concepts." His idea predated modern computers, and so did not directly envision current implementations. He instead expected to see a very sophisticated mechanical card filing system. This is not at all unlike the crosslinking of web pages; only the physical expression really differs.
Ted Nelson coined the term "hypertext," and had a vision ( Project Xanadu ) that in many ways exceeds what has actually been implemented. His model involves (amongst other things) the following components:
Single sources of documents
Sophisticated quoting of source documents
A royalty scheme to allow both original sources and subsequent collectors/linkers of information to profit from the use of valued information.
The original vision, now thirty years old, has still not yet been fully implemented. Partial implementations include:
Zigzag - Xanadu "Hyperstructure Kit"
A "shareware" toolkit available for Unix-like systems such as Linux, using the CURSES terminal-based interface, along with Perl.
There is an Australian site running a web site partially implementing Xanadu.
My Spreadsheets material has a further discussion of ZigZag and its parallels to spreadsheets.
In Fenfire, all applications store data in a single RDF graph. In RDF, " anyone [is] (technically) allowed to say anything about anything;" for Fenfire, this means that any application in the system can add information to any "object" created by itself or by any other application.
It is a successor project to Gzz , which had to be cancelled since free software projects have problems with use of patented technologies...
Understanding how the web and related technologies are, can be, and should be used is a task of understanding the use of Media. The person that first communicated a coherent understanding of the use of media was the late Marshall McLuhan.