Wikis were inspired in part by Apple (Apple Inc.)'s HyperCard program, which allowed users to create virtual “card stacks” of information with a host of connections, or links, among the various cards. HyperCard in turn drew upon an idea suggested by Vannevar Bush (Bush, Vannevar) in his 1945 Atlantic Monthly article As We May Think. There Bush envisioned the memex, a machine that would allow readers to annotate and create links between articles and books recorded on microfilm. HyperCard's “stacks” implemented a version of Bush's vision, but the program relied upon the user to create both the text and the links. For example, one might take a musical score of a symphony and annotate different sections with different cards linked together.

Bush also had imagined that memex users might share what he called “trails,” a record of their individual travels through a textual universe. Cunningham's wiki software expanded this idea by allowing users to comment on and change one another's text. Perhaps the best-known use of wiki software is Wikipedia, an online encyclopaedia using the model of open-source software (open source) development. Individuals write articles and post them on Wikipedia, and these articles are then open for vetting and editing by the community of Wikipedia readers, rather than by a single editor and fact-checker. Just as open-source software—such as the Linux operating system and the Firefox Web browser—has been developed by nonprofit communities, so too is Wikipedia a nonprofit effort.

For those who challenge this model of development, Cunningham and his followers have adopted an interesting position. It is always going to be the case that certain individuals will maliciously attempt to thwart open-source Web sites such as Wikipedia by introducing false or misleading content. Rather than worrying about every user's actions and intentions, proponents of wiki software rely on their community of users to edit and correct what are perceived to be errors or biases. Although such a system is certainly far from foolproof, wikis stand as an example of the origin of an Internet counterculture that has a basic assumption of the goodness of people.

In addition to encyclopaedias, wiki software is used in a wide variety of contexts to facilitate interaction and cooperation in projects at various scales. Manuals have been written using the wiki model, and individuals have adapted wiki software to serve as personal information organizers on personal computers (personal computer). It remains to be seen to what extent wiki software will provide a foundation for what some computer scientists refer to as Web 2.0, the web of social software that will enmesh users in both their real and virtual-reality (virtual reality) workplaces.