Wiki
A wiki 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 – is a Hawaiian word meaning 'quick'.
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. Wiki engines usually allow content to be written using a lightweight markup language and sometimes edited with the help of a rich-text editor. 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 ; 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.
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".
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. 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. The English-language Wikipedia has the largest collection of articles, standing at as of .
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:- "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
Example of syntax
A short section of the 1865 novel Alice's Adventures in Wonderland rendered in wiki markup:| Wiki markup | Equivalent in HTML | Output shown to readers |
"I've had nothing yet," Alice replied in an offended tone, "so I can't take more." "You mean you can't take less," said the Hatter. "It's very easy to take more than nothing." | "Take some more tea," the March Hare said to Alice, very earnestly. "I've had nothing yet," Alice replied in an offended tone, "so I can't take more." "You mean you can't take less," said the Hatter. "It's very easy to take more than nothing." | "Take some more tea," the March Hare said to Alice, very earnestly. "I've had nothing yet," Alice replied in an offended tone, "so I can't take more." "You mean you can't take less," said the Hatter. "It's very easy to take more than nothing." |
Visual editing
While wiki engines have traditionally offered source editing to users, in recent years some implementations have added a rich text editing mode. This is usually implemented, using JavaScript, as an interface which translates formatting instructions chosen from a toolbar into the corresponding wiki markup or HTML. This is generated and submitted to the server transparently, shielding users from the technical detail of markup editing and making it easier for them to change the content of pages. An example of such an interface is the VisualEditor in MediaWiki, the wiki engine used by Wikipedia. WYSIWYG editors may not provide all the features available in wiki markup, and some users prefer not to use them, so a source editor will often be available simultaneously.Version history
Some wiki implementations keep a record of changes made to wiki pages, and may store every version of the page permanently. This allows authors to revert a page to an older version to rectify a mistake, or counteract a malicious or inappropriate edit to its content.These stores are typically presented for each page in a list, called a "log" or "edit history", available from the page via a link in the interface. The list displays metadata for each revision to the page, such as the time and date of when it was stored, and the name of the person who created it, alongside a link to view that specific revision. A diff feature may be available, which highlights the changes between any two revisions.
Edit summaries
The edit history view in many wiki implementations will include edit summaries written by users when submitting changes to a page. Similar to the function of a log message in a revision control system, an edit summary is a short piece of text which summarizes and perhaps explains the change, for example "Corrected grammar" or "Fixed table formatting to not extend past page width". It is not inserted into the article's main text.Navigation
Traditionally, wikis offer free navigation between their pages via hypertext links in page text, rather than requiring users to follow a formal or structured navigation scheme. Users may also create indexes or table of contents pages, hierarchical categorization via a taxonomy, or other forms of ad hoc content organization. Wiki implementations can provide one or more ways to categorize or tag pages to support the maintenance of such index pages, such as a backlink feature which displays all pages that link to a given page. Adding categories or tags to a page makes it easier for other users to find it.Most wikis allow the titles of pages to be searched amongst, and some offer full text search of all stored content.
Navigation between wikis
Some wiki communities have established navigational networks between each other using a system called WikiNodes. A WikiNode is a page on a wiki which describes and links to other, related wikis. Some wikis operate a structure of neighbors and delegates, wherein a neighbor wiki is one which discusses similar content or is otherwise of interest, and a delegate wiki is one which has agreed to have certain content delegated to it. WikiNode networks act as webrings which may be navigated from one node to another to find a wiki which addresses a specific subject.Linking to and naming pages
The syntax used to create internal hyperlinks varies between wiki implementations. Beginning with the WikiWikiWeb in 1995, most wikis used camel case to name pages, which is when words in a phrase are capitalized and the spaces between them removed. In this system, the phrase "camel case" would be rendered as "CamelCase". In early wiki engines, when a page was displayed, any instance of a camel case phrase would be transformed into a link to another page named with the same phrase.While this system made it easy to link to pages, it had the downside of requiring pages to be named in a form deviating from standard spelling, and titles of a single word required abnormally capitalizing one of the letters. Some wiki implementations attempt to improve the display of camel case page titles and links by reinserting spaces and possibly also reverting to lower case, but this simplistic method is not able to correctly present titles of mixed capitalization. For example, "Kingdom of France" as a page title would be written as "KingdomOfFrance", and displayed as "Kingdom Of France".
To avoid this problem, the syntax of wiki markup gained free links, wherein a term in natural language could be wrapped in special characters to turn it into a link without modifying it. The concept was given the name in its first implementation, in UseModWiki in February 2001. In that implementation, link terms were wrapped in a double set of square brackets, for example
It is typically possible for users of a wiki to create links to pages that do not yet exist, as a way to invite the creation of those pages. Such links are usually differentiated visually in some fashion, such as being colored red instead of the default blue, which was the case in the original WikiWikiWeb, or by appearing as a question mark next to the linked words.
History
was the first wiki. Ward Cunningham started developing it in 1994, and installed it on the Internet domain c2.com on March 25, 1995. Cunningham gave it the name after remembering a Honolulu International Airport counter employee telling him to take the "Wiki Wiki Shuttle" bus that runs between the airport's terminals, later observing that "I chose wiki-wiki as an alliterative substitute for 'quick' and thereby avoided naming this stuff quick-web."Cunningham's system was inspired by his having used Apple's hypertext software HyperCard, which allowed users to create interlinked "stacks" of virtual cards. HyperCard, however, was single-user, and Cunningham was inspired to build upon the ideas of Vannevar Bush, the inventor of hypertext, by allowing users to "comment on and change one another's text". Cunningham says his goals were to link together people's experiences to create a new literature to document programming patterns, and to harness people's natural desire to talk and tell stories with a technology that would feel comfortable to those not used to "authoring".
Wikipedia became the most famous wiki site, launched in January 2001 and entering the top ten most popular websites in 2007. In the early 2000s, wikis were increasingly adopted in enterprise as collaborative software. Common uses included project communication, intranets, and documentation, initially for technical users. Some companies use wikis as their collaborative software and as a replacement for static intranets, and some schools and universities use wikis to enhance group learning. On March 15, 2007, the word wiki was listed in the online Oxford English Dictionary.