A wiki (/ˈwɪki/ ⓘ WICK-ee) is a form of hypertext publication on the internet which is collaboratively edited and managed by its audience directly through a web browser. A typical wiki contains multiple pages that can either be edited by the public or limited to use within an organization for maintaining its internal knowledge base. Its name derives from the first user-editable website called WikiWikiWeb – wiki (pronounced [wiki][note 1]) is a Hawaiian word meaning ‘quick’.[1][2][3][4]
Wikis are powered by wiki software, also known as wiki engines. Being a form of content management system, these differ from other web-based systems such as blog software or static site generators in that the content is created without any defined owner or leader. Wikis have little inherent structure, allowing one to emerge according to the needs of the users.[5] Wiki engines usually allow content to be written using a lightweight markup language and sometimes edited with the help of a rich-text editor.[6] There are dozens of different wiki engines in use, both standalone and part of other software, such as bug tracking systems. Some wiki engines are free and open-source, whereas others are proprietary. Some permit control over different functions (levels of access); for example, editing rights may permit changing, adding, or removing material. Others may permit access without enforcing access control. Further rules may be imposed to organize content. In addition to hosting user-authored content, wikis allow those users to interact, hold discussions, and collaborate.[7]
There are hundreds of thousands of wikis in use, both public and private, including wikis functioning as knowledge management resources, note-taking tools, community websites, and intranets. Ward Cunningham, the developer of the first wiki software, WikiWikiWeb, originally described wiki as “the simplest online database that could possibly work”.[8]
The online encyclopedia project Wikipedia is the most popular wiki-based website, as well being one of the internet’s most popular websites, having been ranked consistently as such since at least 2007.[9] Wikipedia is not a single wiki but rather a collection of hundreds of wikis, with each one pertaining to a specific language, making it the largest reference work of all time.[10] The English-language Wikipedia has the largest collection of articles, standing at 7,128,285 as of January 2026.[11]
Characteristics
In their 2001 book The Wiki Way: Quick Collaboration on the Web, Ward Cunningham and co-author Bo Leuf described the essence of the wiki concept:[12][13]
- “A wiki invites all users—not just experts—to edit any page or to create new pages within the wiki website, using only a standard ‘plain-vanilla’ Web browser without any extra add-ons.”
- “Wiki promotes meaningful topic associations between different pages by making page link creation intuitively easy and showing whether an intended target page exists or not.”
- “A wiki is not a carefully crafted site created by experts and professional writers and designed for casual visitors. Instead, it seeks to involve the typical visitor/user in an ongoing process of creation and collaboration that constantly changes the website landscape.”
Editing
“Wikitext” redirects here. For the Wikipedia help page, see Help:Wikitext.
Source editing
Some wikis will present users with an edit button or link directly on the page being viewed. This will open an interface for writing, formatting, and structuring page content. The interface may be a source editor, which is text-based and employs a lightweight markup language (also known as wikitext, wiki markup, or wikicode), or a visual editor. For example, in a source editor, starting lines of text with asterisks could create a bulleted list.
The syntax and features of wiki markup languages for denoting style and structure can vary greatly among implementations. Some allow the use of HTMLTooltip Hypertext Markup Language and CSSTooltip Cascading Style Sheets,[14] while others prevent the use of these to foster uniformity in appearance.