- A wiki invites all users to edit any page or to create new pages within the wiki Web site, using only a plain-vanilla Web browser without any extra add-ons.
- Wiki promotes meaningful topic associations between different pages by making page link creation almost intuitively easy and showing whether an intended target page exists or not.
- A wiki is not a carefully crafted site for casual visitors. Instead, it seeks to involve the visitor in an ongoing process of creation and collaboration that constantly changes the Web site landscape.
A wiki enables communities to write documents collaboratively, using a simple markup language and a web browser. A single page in a wiki website is referred to as a "wiki page", while the entire collection of pages, which are usually well interconnected by hyperlinks, is "the wiki". A wiki is essentially a database for creating, browsing, and searching through information. A wiki allows for non-linear, evolving, complex and networked text, argument and interaction.[12]
A defining characteristic of wiki technology is the ease with which pages can be created and updated. Generally, there is no review before modifications are accepted. Many wikis are open to alteration by the general public without requiring them to register user accounts. Many edits can be made in real-time and appear almost instantly online. This can facilitate abuse of the system. Private wiki servers require user authentication to edit pages, and sometimes even to read them.
Maged N. Kamel Boulos, Cito Maramba and Steve Wheeler write that it is the "openness of wikis that gives rise to the concept of 'Darwikinism', which is a concept that describes the 'socially Darwinian process' that wiki pages are subject to. Basically, because of the openness and rapidity that wiki pages can be edited, the pages undergo a natural selection process like that which nature subjects to living organisms. 'Unfit' sentences and sections are ruthlessly culled, edited and replaced if they are not considered 'fit', which hopefully results in the evolution of a higher quality and more relevant page. Whilst such openness may invite 'vandalism' and the posting of untrue information, this same openness also makes it possible to rapidly correct or restore a 'quality' wiki page."[13]
Editing wiki pages
There are many different ways in which wikis have users edit the content. Ordinarily, the structure and formatting of wiki pages are specified with a simplified markup language, sometimes known as wikitext (for example, starting a line of text with an asterisk often sets up a bulleted list). The style and syntax of wikitexts can vary greatly among wiki implementations, some of which also allow HTML tags. Designers of wikis often take this approach because HTML, with its many cryptic tags, is not very legible, making it hard to edit. Wikis therefore favour plain-text editing, with fewer and simpler conventions than HTML, for indicating style and structure. Although limiting access to HTML and Cascading Style Sheets (CSS) of wikis limits user ability to alter the structure and formatting of wiki content, there are some benefits. Limited access to CSS promotes consistency in the look and feel, and having JavaScript disabled prevents a user from implementing code that may limit access for other users.| MediaWiki syntax | Equivalent HTML | Rendered output |
|---|---|---|
| "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." |
<p>"Take some more <a href="/wiki/Tea"
title="Tea">tea</a>," the March Hare said to Alice, very
earnestly.</p> <p>"I've had <b>nothing</b> yet," Alice replied in an offended tone, "so I can't take more."</p> <p>"You mean you can't take <i>less</i>?" said the Hatter. "It's very easy to take <i>more</i> than nothing."</p> |
"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." |
Most wikis keep a record of changes made to wiki pages; often, every version of the page is stored. This means that authors can revert to an older version of the page, should it be necessary because a mistake has been made or the page has been vandalized. Many implementations, like MediaWiki, allow users to supply an edit summary when they edit a page; this is a short piece of text summarising the changes. It is not inserted into the article, but is stored along with that revision of the page, allowing users to explain what has been done and why; this is similar to a log message when making changes to a revision-control system.
Within the text of most pages there are usually a large number of hypertext links to other pages. This form of non-linear navigation is more "native" to wiki than structured/formalized navigation schemes. That said, users can also create any number of index or table-of-contents pages, with hierarchical categorization or whatever form of organization they like. These may be challenging to maintain by hand, as multiple authors create and delete pages in an ad hoc manner. Wikis generally provide one or more ways to categorize or tag pages to support the maintenance of such index pages.
Most wikis have a backlink feature, which displays all pages that link to a given page.
It is typical in a wiki to create links to pages that do not yet exist, as a way to invite others to share what they know about a subject new to the wiki.
Linking and creating pages
Links are created using a specific syntax, the so-called "link pattern" (also see CURIE). Originally, most wikis used CamelCase to name pages and create links. These are produced by capitalizing words in a phrase and removing the spaces between them (the word "CamelCase" is itself an example). While CamelCase makes linking very easy, it also leads to links which are written in a form that deviates from the standard spelling. CamelCase-based wikis are instantly recognizable because they have many links with names such as "TableOfContents" and "BeginnerQuestions." It is possible for a wiki to render the visible anchor for such links "pretty" by reinserting spaces, and possibly also reverting to lower case. However, this reprocessing of the link to improve the readability of the anchor is limited by the loss of capitalization information caused by CamelCase reversal. For example, "RichardWagner" should be rendered as "Richard Wagner," whereas "PopularMusic" should be rendered as "popular music". There is no easy way to determine which capital letters should remain capitalized. As a result, many wikis now have "free linking" using brackets, and some disable CamelCase by default.Implementations
Wiki software is a type of collaborative software that runs a wiki system, allowing web pages to be created and edited using a common web browser. It is usually implemented as an application server that runs on one or more web servers. The content is stored in a file system, and changes to the content are stored in a relational database management system. A commonly implemented software package is MediaWiki, which runs this encyclopedia. See the List of wiki software for further information.Alternatively, personal wikis run as a standalone application on a single computer. WikidPad is an example. Or even single local HTML file with JavaScript inside - like TiddlyWiki.
Wikis can also be created on a "wiki farm", where the server side software is implemented by the wiki farm owner. PBwiki, Socialtext, Wetpaint, and Wikia are popular examples of such services. Some wiki farms can also make private, password-protected wikis. Note that free wiki farms generally contain advertising on every page. For more information, see Comparison of wiki farms.
