Wiki

Editing

"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>

Visual editing

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While wiki engines have traditionally offered source editing to users, as early as 2013^[16], 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.

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.

Linking to and naming pages

The syntax used to create internal hyperlinks varies between wiki implementations. Beginning with WikiWikiWeb in 1995, most wikis used camel case to name pages,^[19] 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 (e.g. "WiKi" instead of "Wiki"). 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 (called wikilinks), 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.^[20] In that implementation, link terms were wrapped in a double set of square brackets, for example [[Kingdom of France]]. This syntax was adopted by a number of later wiki engines.

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.

Access control

The four basic types of users who participate in wikis are readers, authors, wiki administrators and system administrators. System administrators are responsible for the installation and maintenance of the wiki engine and the container web server. Wiki administrators maintain content and, through having elevated privileges, are granted additional functions (including, for example, preventing edits to pages, deleting pages, changing users' access rights, or blocking them from editing).^[30]

Controlling changes

Wikis are generally designed with a soft security philosophy in which it is easy to correct mistakes or harmful changes, rather than attempting to prevent them from happening in the first place. This allows them to be very open while providing a means to verify the validity of recent additions to the body of pages. Most wikis offer a recent changes page which shows recent edits, or a list of edits made within a given time frame.^[31] Some wikis can filter the list to remove edits flagged by users as "minor" and automated edits.^[32] The version history feature allows harmful changes to be reverted quickly and easily.^[17]

Some wiki engines provide additional content control, allowing remote monitoring and management of a page or set of pages to maintain quality. A person willing to maintain pages will be alerted of modifications to them, allowing them to verify the validity of new editions quickly.^[33] Such a feature is often called a watchlist.

Some wikis also implement patrolled revisions, in which editors with the requisite credentials can mark edits as being legitimate. A flagged revisions system can prevent edits from going live until they have been reviewed.^[34]

Wikis may allow any person on the web to edit their content without having to register an account on the site first (anonymous editing), or require registration as a condition of participation.^[35] On implementations where an administrator is able to restrict editing of a page or group of pages to a specific group of users, they may have the option to prevent anonymous editing while allowing it for registered users.^[36]

Trustworthiness and reliability of content

Critics of publicly editable wikis argue that they could be easily tampered with by malicious individuals, or even by well-meaning but unskilled users who introduce errors into the content. Proponents maintain that these issues will be caught and rectified by a wiki's community of users.^[7][21] High editorial standards in medicine and health sciences articles, in which users typically use peer-reviewed journals or university textbooks as sources, have led to the idea of expert-moderated wikis.^[37] Wiki implementations retaining and allowing access to specific versions of articles has been useful to the scientific community, by allowing expert peer reviewers to provide links to trusted version of articles which they have analyzed.^[38]

Security

Trolling and cybervandalism on wikis, where content is changed to something deliberately incorrect or a hoax, offensive material or nonsense is added, or content is maliciously removed, can be a major problem. On larger wiki sites it is possible for such changes to go unnoticed for a long period.

In addition to using the approach of soft security for protecting themselves, larger wikis may employ sophisticated methods, such as bots that automatically identify and revert vandalism. For example, on Wikipedia, the bot ClueBot NG uses machine learning to identify likely harmful changes, and reverts these changes within minutes or even seconds.^[39]

Disagreements between users over the content or appearance of pages may cause edit wars, where competing users repetitively change a page back to a version that they favor. Some wiki software allows administrators to prevent pages from being editable until a decision has been made on what version of the page would be most appropriate.^[8]

Some wikis may be subject to external structures of governance which address the behavior of persons with access to the system, for example in academic contexts.^[29]

Applications

The English Wikipedia has the largest user base among wikis on the World Wide Web^[40] and ranks in the top 10 among all Web sites in terms of traffic.^[41] Other large wikis include the WikiWikiWeb, Memory Alpha, Wikivoyage, and previously Susning.nu, a Swedish-language knowledge base. Medical and health-related wiki examples include Ganfyd, an online collaborative medical reference that is edited by medical professionals and invited non-medical experts.^[42] Many wiki communities are private, particularly within enterprises. They are often used as internal documentation for in-house systems and applications. Some companies use wikis to allow customers to help produce software documentation.^[43] A study of corporate wiki users found that they could be divided into "synthesizers" and "adders" of content. Synthesizers' frequency of contribution was affected more by their impact on other wiki users, while adders' contribution frequency was affected more by being able to accomplish their immediate work.^[44] From a study of thousands of wiki deployments, Jonathan Grudin concluded careful stakeholder analysis and education are crucial to successful wiki deployment.^[45]

In 2005, the Gartner Group, noting the increasing popularity of wikis, estimated that they would become mainstream collaboration tools in at least 50% of companies by 2009.^{[46][needs update]} Wikis can be used for project management.^{[47][48][unreliable source]} Wikis have also been used in the academic community for sharing and dissemination of information across institutional and international boundaries.^[49] In those settings, they have been found useful for collaboration on grant writing, strategic planning, departmental documentation, and committee work.^[50] In the mid-2000s, the increasing trend among industries toward collaboration placed a heavier impetus upon educators to make students proficient in collaborative work, inspiring even greater interest in wikis being used in the classroom.^[8]

Wikis have found some use within the legal profession and within the government. Examples include the Central Intelligence Agency's Intellipedia, designed to share and collect intelligence assessments, DKosopedia, which was used by the American Civil Liberties Union to assist with review of documents about the internment of detainees in Guantánamo Bay;^[51] and the wiki of the United States Court of Appeals for the Seventh Circuit, used to post court rules and allow practitioners to comment and ask questions. The United States Patent and Trademark Office operates Peer-to-Patent, a wiki to allow the public to collaborate on finding prior art relevant to the examination of pending patent applications. Queens, New York has used a wiki to allow citizens to collaborate on the design and planning of a local park. Cornell Law School founded a wiki-based legal dictionary called Wex, whose growth has been hampered by restrictions on who can edit.^[36]

In academic contexts, wikis have also been used as project collaboration and research support systems.^[52][53]

Growth factors

A study of several hundred wikis in 2008 showed that a relatively high number of administrators for a given content size is likely to reduce growth;^[57] access controls restricting editing to registered users tends to reduce growth; a lack of such access controls tends to fuel new user registration; and that a higher ratio of administrators to regular users has no significant effect on content or population growth.^[58]

Sources

• Ebersbach, Anja (2008), Wiki: Web Collaboration, Springer Science+Business Media, ISBN 978-3-540-35150-4