A wiki (Hawaiian for “fast”) is a website whose content can not only be read by visitors, but also edited and changed directly in the web browser (Web 2.0 application).

The goal is often to gather experience and knowledge jointly (collective intelligence) and to document it in a form understandable for the target group. For this purpose, the authors jointly develop texts, which may be supplemented by photos or other media (collaborative writing, e-collaboration). This is made possible by a simplified content management system, the so-called wiki software or wiki engine.

The best-known wiki is the online encyclopedia Wikipedia, which uses the wiki software MediaWiki . In addition, many companies also use wikis as part of the knowledge management system in their intranet (across locations), see Enterprise Wiki. A single document, a wiki page, can be changed with just a few clicks ( Edit button and Save or Publish button). For this purpose, the wiki page is usually stored in the form of wikitext, an easy-to-learn markup language.

The image at the top right shows the wikitext of this wiki page in edit mode.


The co-inventor of the wikis, Ward Cunningham, chose the name Wiki because of a trip to Hawaii. Upon arrival at the airport on Oahu, he saw the name Wiki Wiki for the express bus there. He took over the doubling, which in Hawaiian stands for an increase (“very fast”). Cunningham considers Wiki to be an abbreviation for the actual name of his wiki, WikiWikiWeb.

Since the term is older than the Wiki concept or Wikipedia, it appears accordingly already in older dictionaries and also in the writer Jack London. In his work Martin Eden from 1908 it says: This is my latest, very different from anything I have done before… It’s a Hawaiian story. I called it Wiki-Wiki.

Because of its success, most people think of Wikipedia when they hear the term wiki. Often they even use the term as an abbreviation for Wikipedia, unaware that it is the name for a certain type of software and its application.

Definition of Wiki

There is no generally accepted definition of wikis and no consensus on what characteristics make up a wiki. Some of the characteristics listed in the literature are vague (such as “simplicity”) or not exclusive to wikis (such as page content versioning). For example, linking pages to hypertext is typical for many wikis, but not mandatory: a wiki can also be organized like a manual with a general outline. Other characteristics discussed are openness, collaboration and self-determination.

Andrew Lih, for example, succinctly defines the wiki concept as the “radical idea of allowing anyone to openly edit every page of a website”. For Ebersbach, Glaser and Heigl, wiki software enables “the emergence of associative hypertexts with non-linear navigation structures”. Ziko van Dijk defines:

“A wiki is a medium for the production and reception of collaborative content. Content is collaborative if it can, may and should be created and modified by more than one person.

The content in the wiki is separated into main content and secondary content; the latter is used to communicate via the main content and the wiki.

A wiki has a macrostructure that allows only one segment on the same topic (unique principle)”.

The definition determines which collaborative systems you want to include, regardless of whether they have the term “wiki” in their names or not. Systems for the business world, the so-called enterprise wikis, often make it possible, for example, to set up closed communication rooms for small groups or to use a built-in calendar. Florian L. Mayer speaks here of “complete systems with wiki functionality”.

Wiki functioning

As a significant difference to other content management systems (CMS), wiki software offers fewer design options for the layout and design of websites. The primary function, on the other hand, is an editing mode for each wiki page, which allows even a newbie to change the text and content of the page without much training. To do this, the wiki page is often opened in a WYSIWYG editor in edit mode or displayed in an easy-to-learn, simplified markup language (such as wikitext) (or optionally both). As a rule, both variants allow font markup, linking, lists and enumerations as well as the possibility of transclusions for repetitive content.

In contrast to content management systems with their sometimes precisely regulated workflows, for example in editorial systems, wikis rely on the philosophy of open access: ideally, every user can read and edit every entry. Wikis are considered to have an advantage over a classic CMS if a high number of users enter information, so that a critical mass is reached in the medium and it becomes a “self-runner”. However, there are also wiki systems that allow access control (e.g. via Access Control List) for certain pages and user groups (e.g. departments of a company).

An essential feature of most wiki products is version control, which allows users to quickly restore a previous version of a page in the event of errors or vandalism, which are hardly avoidable due to open access.

As usual with hypertexts, the individual pages of a wiki are connected by cross-references (hyperlinks); the title of a page usually also serves as a link address. Links to non-existent pages are then not displayed as errors, but a form appears to create the new page. Networking with other popular wiki services is partly made possible by so-called InterWiki links.

Most systems are released as free software, often under a version of the common GNU General Public License (GPL). Many wiki software systems are modular and offer their own programming interface that allows the user to write their own extensions without knowing the entire source code.

A wiki can be publicly accessible on the World Wide Web, used in local networks only for a certain user group (e.g. as an intranet) or used on a single computer for personal information organization, for example in the form of a desktop wiki. Examples of desktop wiki software include AcroWiki for Palm OS, Tomboy and Zim for Linux, VoodooPad for macOS, Gluebox (platform independent), ConnectedText and WikidPad for Windows, and TiddlyWiki, which runs client-side (without server) as JavaScript in any browser. In the case of publicly accessible wikis, there may be restrictions, for example, due to an obligation to register, so that a user account is associated with additional access rights.

Divisions of wikis

Wikis can be used for different purposes and different environments and can be operated with different software. There is no generally accepted typology and terminology, but trends can be identified.

Wikis are often referred to according to their very specific function or topic, so a variety of names have emerged: “Fanwiki” for pop culture content, “Stadtwiki” or “Regiowiki” for the history or current civil society of a local entity, “Enterprise Wiki” (“Enterprise Wiki”, “Company Wiki”, “Business Wiki”, “Organization Wiki”) for a work platform in the company or possibly another organization, etc. However, a “school wiki” can also be used in very different ways, namely as an (internal) learning platform, public platform for learners or as a real replacement for a conventional website.

In the literature, there are also approaches for a two- or three-division of the wikis. Open and public wikis such as Wikipedia are opposed to the closed and non-public (internal) wikis of an organization. Van Dijk uses, among other things, a distinction according to who should benefit from the wiki. Recipient-oriented wikis such as Wikipedia are intended to serve readers; Owner-oriented wikis such as enterprise wikis help to realize corporate goals; Modicient-oriented wikis are, for example, learning platforms for the benefit of the editing learners; and content-driven wikis like Wikimedia Commons help collect and deliver content.

History and applications

The development of the wiki as a medium is closely linked to the World Wide Web. It was only through this that it became a successful model, even if its predecessors date back to the 1970s. The changeability of the pages by anyone also consistently implements an original idea of the World Wide Web.

In software development, the benefits of wikis for knowledge management in a collaborative environment were first recognized, which is probably due to the technical affinity of the employees. A wiki system can be used in software development, in particular the creation of documentation, for the management of software errors or for coordination among software developers. The first wikis were developed in the mid-1990s by software designers for product management in IT projects. Especially in development projects of open source software – such as Apache or – in which people scattered across continents work together, wikis play a key role. Today, wikis are used in a variety of applications where content flexibility counts more than a representative layout. This includes documentation in business, science and culture.


One of the first forerunners of the wiki was the ZOG database system developed at Carnegie-Mellon University in 1972, which was designed for multiple users and presented the data in structured text frames; they were connected by hyperlinks.

This system was extended in 1981 by Donald McCracken and Robert Akscyn to the Knowledge Management System (KMS), in which changes to the data sheets were immediately visible throughout the network. In this system, graphics and images could already be integrated, they could also be provided with hyperlinks.

Also based on ZOG was Janet Walker’s Document Examiner, which was used from 1985 to display computer instructions. This hypertext system, in which the texts were displayed in a scrollable screen window, was further developed by Xerox in the same year into the Note Cards system, from which Apple’s HyperCard system (initially under the name WildCard) finally emerged in 1987.

Ward Cunningham, inventor of the wiki
Ward Cunningham, inventor of Wiki

This system influenced Ward Cunningham decisively with his WikiWikiWeb, as it already allowed different types of cards, one of which could stand for users, one for projects and one for the ideas themselves. Also, in Cunningham’s evolution of the system, it was possible to create new maps by clicking on links to non-existent content.

Tim Berners-Lee, who made decisive contributions to HTML and the World Wide Web from 1989 onwards, had pursued similar ideas at the beginning of his work on hypertext systems, as he believed that this tool should be used primarily for the collaborative creation of texts in the scientific community. Consequently, Berners-Lee’s first web browser WorldWideWeb (1990/1991) was suitable for both displaying and editing websites. From a historical perspective, he describes his ideas in his book “Weaving The Web”. Nevertheless, the non-collaborative creation of websites initially prevailed on the Web, which was achieved through restrictive user rights for the pages on the servers.

The WikiWikiWeb

The first real wiki hosted on the web, WikiWikiWeb, was conceived by the American software author Ward Cunningham as a knowledge management tool within the framework of the design pattern theory in 1994 based on the HyperCard systems. It dealt with software design in the context of object-oriented programming. On March 25, 1995, it was made available to the public via the Internet.

Cunningham’s concept met with great interest in the software development community, which grew rapidly. In December 1995, the pages of WikiWikiWeb already contained 2.4 MB of storage space, at the end of 1997, it was 10 MB and at the end of 2000 62 MB.

Wikis in the late 1990s

Shortly after the commissioning of WikiWikiWeb, the first clones of the software were created. Wikis quickly became a popular tool in the free software scene, where they were used as a tool to support communication and idea organization among developers. Cunningham also supported this development by publishing his own clone of his software, called Wiki Base. However, tensions soon arose between WikiWikiWeb and some clones, as Cunningham expected Wiki Base users to add their own improvements to the source code of his own wiki, but this rarely happened.

One of the most important clones of Wiki Base was CvWiki, written by Peter Merel in 1997. This resulted in 1999 in the UseModWiki, which is still used today in the MeatballWiki, one of the most popular software wikis. UseModWiki was also Wikipedia’s wiki engine in the early days until it was replaced by MediaWiki in 2002.

In 1998, TWiki was released, the first wiki software based on text files, this system is particularly suitable for smaller wikis (e.g. desktop and company wikis), in which higher performance can be achieved. In 1999, PhpWiki was the first wiki engine based on the PHP programming language.

Until 2001, wikis as a medium were largely confined to the software development scene, so public interest in them outside of this specialized scene was limited. Nevertheless, other software concepts have already been used to develop collaborative web portals with similar goals to Everything2. The first real wiki portal developed on a topic other than the software was the online travel guide World66, founded in 1999 by a Dutch company that was one of the first to try to integrate the concept of free content into a profitable business model.

Between 1998 and 2000, tensions arose within the WikiWikiWeb itself as contributions moved further and further away from the original topic of the wiki. This led to a confrontation between two groups: While the WikiReductionists wanted to continue to see the focus of the wiki on object-oriented software programming, the WikiConstructionists felt that there should also be room for other, more general topics in the WikiWikiWeb, especially those concerning the wiki concept as such (so-called WikiOnWiki topics).

This led to the split in 2000 and the founding of the MeatballWiki, which, in addition to discussing the wiki idea itself, also dealt with more general topics such as copyright or the cyberpunk movement. The MeatballWiki and several other websites created in this dispute were called SisterSites and linked directly from the WikiWikiWeb. From this wiki come numerous ideas that should promote the popularization of the wiki idea, such as the TourBusStop, a tour through different wikis, the WikiNode as the node of a wiki and the WikiIndex (about 22,000 pages) as a database of as many wikis as possible.

Wikipedia and the popularization of the concept: 2001 to 2005

The popularization of the wiki concept goes back to the online encyclopedia Wikipedia. Between 1999 and 2000, the American company Bomis had developed the idea of an encyclopedia created on the Internet. However, the Nupedia project, which was launched in 2000, was initially unsuccessful because the process of creating the entries was based on the peer review process and was therefore very lengthy. Towards the end of the year, Bomis’ founder Jimmy Wales and Wales employed Larry Sanger developed a wiki extension, which went online on January 15, 2001, on the separate domain and developed into a great success in the course of the year, especially after a report in the online magazine Slashdot. In the same year, other language versions were launched. By 2005, the number of pages had grown to over one million and Wikipedia had become one of the most visited websites.

In order to meet the growing demands of Wikipedia, the MediaWiki software was developed in 2002. She introduced as an innovation that the links could receive a free text for the first time, before the so-called CamelCase spelling was common, in which the words were not separated by spaces. MediaWiki was particularly designed for scalability to cope with the rapidly increasing number of users.

In the following years, new wiki-based web portals were founded, partly from the Wikipedia community, but also partly from the meatball community. These included the Enciclopedia Libre, a spin-off of the Spanish-language Wikipedia founded in 2002,, a Swedish-language mixture of encyclopedia and web forum, the online travel guide Wikitravel, founded in 2003, the SourceWatch project for documenting lobbying organizations, and the Wikinews, Wiktionary, Wikibooks, Wikisource, Wikiquote, and Wikispecies wikis, known as sister projects of Wikipedia. The wiki concept was thus adapted to different types of texts, with varying degrees of success. The first significant modification of the Wikipedia concept was developed in 2003 with Wikinfo, in which different perspectives on various topics were allowed; however, the success lagged far behind that of Wikipedia.

Commercial wiki farms, which often offer their services free of charge, have led to the fact that there is gradually a separate wiki for almost every possible topic. A particularly great success were the so-called fan wikis, which – in addition to the lexical treatise – enabled a new form of collaboratively created fan fiction. Especially in science fiction (e.g. Memory Alpha), fantasy and comics, some wikis were able to achieve high numbers of articles and participants. Wikis such as Uncyclopedia, Stupidedia and Kamelopedia have also established themselves in the field of humor.

Wikis as Mass Media: Development since 2005

The success of Wikipedia led to various efforts to improve the wiki concept. In the area of wikis designed as an encyclopedia, Ulrich Fuchs and Larry Sanger independently developed the projects Wikiweise and Citizendium, in which the wiki concept is restricted and instead, an increase in quality is to be achieved through a system closer to the traditional editorial working method. At Citizendium, for example, each article has its own responsible maintainer, who is known by his real name. However, both projects have so far been denied a resounding success.

Another development is the extension of traditional web portals of various kinds by wiki functions. In the knowledge portal Google Knol, anyone interested could post texts and determine whether or not to release their content for collaborative editing in the wiki style. The scientific wiki Scholarpedia is based on a similar concept, which is limited to a few special topics and severely restricts the participation opportunities of non-specialists.

Since about 2005, computer-generated databases have been created on a wiki basis, which can be edited and thus improved by web users. These wikis are usually highly structured and make extensive use of templates. Well-known representatives of this wiki form are the web directory, the open directory project extension Chainki and the proprietary music database CDWiki. Wikis were even used to market Internet advertising, such as WikiFox (now discontinued) and ShoppiWiki.

Through software extensions, the wiki concept was extended by the presentation of popular content such as web videos from 2005 and prepared for future expected Internet phenomena such as the semantic web.

In March 2007, the word wiki was added to the Oxford English Dictionary.

A number of regiowikis have been set up specifically for individual cities and their topics. For a long time, the largest in the world was the Stadtwiki Karlsruhe.

Wikis in organizations: Development since 2007

Enterprise Wikis

Inspired by the success of Wikipedia, many companies have begun to build enterprise wikis for knowledge management (also: business wikis, enterprise wikis). Employees should collect the knowledge of their employees within the company and make it transparent. The financial outlay, on the other hand, is usually lower than with conventional systems of knowledge conservation. The use of wikis tends to be more promising with flat hierarchies and in a corporate culture that is as open as possible.

Florian L. Mayer warns in his dissertation against a lack of overlap between boss expectations and reality in the wiki. The knowledge that is stored in wikis only becomes useful for the organization when it can be transformed into business-relevant decisions. Important is not only the “motivation to cooperate”, but also to retrieve content. It is problematic to think that collaboration in general comes about because of collaboration in Wikipedia. In Mayer’s opinion, a wiki does not promote collaboration in the organization, but rather only reflects it. If the wiki observes and evaluates one’s own way of working, this can also harm motivation.

In 2008, for example, 41% of Finland’s top 50 companies used or tested wikis, with another 18% open to wiki use.

According to a study by Forrester Research, the use of enterprise wikis in Enterprise 2.0 will increase tenfold from 2007 to 2013. The management consultancy Gartner estimated that in 2009 about half of the companies installed a wiki.

Basically, corporate wikis can be divided into two groups:

  • Company or department wikis try to capture the knowledge of a company or department.
  • Project-related wikis, on the other hand, are specifically tailored to a single project. Like the associated projects, they often have only a limited lifespan and should often only be accessible to a certain group of people.

Some wikis combine both types and allow the creation of so-called spaces to separate projects from each other in terms of content and user rights.

Wikis in the education sector

Meanwhile, many schools and universities use their own wikis. In 2010, WikiWebs existed at more than 34% of all universities in Germany.

Wiki of History of Technology

The world’s largest technical professional society, the Institute of Electrical and Electronics Engineers (IEEE), which focuses on electrical engineering and computer science, founded a sub-organization called the IEEE Global History Network in 2008. The result was a wiki-based, English-language, freely accessible online database with historical content on the history of technology in these departments. This includes milestones of development as well as oral and written personal experience reports. In 2015, the IEEE Global History Network was incorporated into the broader organization Engineering and Technology History Wiki of the most important US technical professional societies and will continue there.

Wikis for politics

In the sense of participatory theories of democracy, some authors imagine that wikis could revive democracy. One example is a work by the philosopher Wätzold Plaum, according to which draft laws should be drafted according to the “Wikipedia principle”. However, one should prevent a hierarchization as in Wikipedia occurs. He wants citizens to have a say in political decisions online.

In general, participation-oriented theories are also criticized because citizens have different amounts of time and skills to engage politically. With regard to wikis, the question arises whether the results of wiki discussions are actually implemented or only understood as a suggestion. For those who participate in the wiki of a party, it is demotivating if the work in the wiki does not bring them influence and status in the party.

On 11 July 2009, the Institute for Portuguese Democracy (IDP) launched the Constituição 2.0 project in Portugal. Following the example of Wikipedia, a new Portuguese constitution created collectively with the wiki system is to be created. An article in the Israeli Daily Haaretz took up the idea as a way to create a constitution for Israel.

Wiki Software

Wiki software is software that meets the requirements of a wiki. Many applications such as Google Docs, Microsoft Word or Dropbox have features that enable collaboration. What is important is not so much the software used, but the way it is used. However, there is software designed specifically for wikis. First and foremost, this applies to the MediaWiki software, which runs Wikipedia, for example.

Wiki software can help to structure and document knowledge within an organization and thus make it more easily available and usable. In this way, knowledge transfer becomes less dependent on direct interpersonal contact. A wiki can also serve to make organizational structures up to informal networks and experts as contact persons transparent. The choice of suitable wiki software depends on the structure of the organization as well as on the specific purpose.


Wiki systems support editing content differently (e.g. using a WYSIWYG editor). In a company, the login can be synchronized with the login to other software systems (LDAP authentication). A connection to the Office software used can make it possible to directly edit and version text or spreadsheet documents stored in the wiki. Templates can help create similar structured wiki entries.

Knowledge Management Features

  • Content is systematized by assigning it to specific categories and tags.
  • If possible, the search function searches not only the wiki pages themselves, but also text or spreadsheet documents stored in the wiki.
  • Discussion pages are used to compare knowledge and exchange meta-knowledge about a wiki entry or text.
  • Information stored in the company’s ERP system can be connected.
  • For quality assurance, it may be necessary to release a document before it is published (workflow).

User Rights Management

A wiki can merge the created accounts into so-called user groups. This means that the accounts have certain rights, depending on which user groups they belong to. Then a user can only edit some pages from his account, but not all pages. A well-known user group are the administrators, who can, for example, lock accounts.

Such user groups are initially to be understood in a purely technical sense. A user with access to an account in the administrator’s user group is subject to the rules of the wiki community or wiki owner. These rules determine whether and when he is actually allowed to block another account.


A wide distribution of the wiki software contributes to securing the investment in the long term. It can be seen by how many references there are and whether there is an active user community. Users of software are dependent on the software provider making the software permanently available and updated. Open-source software has the advantage that it may be possible to continue it without being dependent on a single provider.

References (sources)