Wikipedia, a free-content online encyclopedia written and maintained by a community of volunteers known as Wikipedians, began with its first edit on 15 January 2001, two days after the domain was registered. It grew out of Nupedia, a more structured free encyclopedia, as a way to allow easier and faster drafting of articles and translations.
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.
MediaWiki is free and open-source wiki software originally developed by Magnus Manske for use on Wikipedia on January 25, 2002, and further improved by Lee Daniel Crocker, after which development has been coordinated by the Wikimedia Foundation. It powers several wiki hosting websites across the Internet, as well as most websites hosted by the Wikimedia Foundation including Wikipedia, Wiktionary, Wikimedia Commons, Wikiquote, Meta-Wiki and Wikidata, which define a large part of the set requirements for the software. Besides its usage on Wikimedia sites, MediaWiki has been used as a knowledge management and content management system on websites such as Fandom, wikiHow and major internal installations like Intellipedia and Diplopedia.
The English Wikipedia is the primary English-language edition of Wikipedia, an online encyclopedia. It was created by Jimmy Wales and Larry Sanger on 15 January 2001, as Wikipedia's first edition.
The German Wikipedia is the German-language edition of Wikipedia, a free and publicly editable online encyclopedia.
The Wikimedia movement is the global community of contributors to the Wikimedia projects, including Wikipedia. This community directly builds and administers these projects with the commitment of achieving this using open standards and software.
Baidu Baike is a semi-regulated Chinese-language collaborative online encyclopedia owned by the Chinese technology company Baidu. The beta version was launched on 20 April 2006, and the official version was launched on 21 April 2008. In November 2019, it had more than 16 million articles and 6.9 million editors. As of February 2022, it has more than 25.54 million entries and 7.5 million editors. It has the largest number of entries in the world of any Chinese-language online encyclopedia.
The Encyclopedia of Earth is an electronic reference about the Earth, its natural environments, and their interaction with society. The Encyclopedia is described as a free, fully searchable collection of articles written by scholars, professionals, educators, and other approved experts, who collaborate and review each other's work. The articles are written in non-technical language and are intended to be useful to students, educators, scholars, and professionals, as well as to the general public. The authors, editors, and even copy editors are attributed on the articles with links to biographical pages on those individuals.
The Vietnamese Wikipedia is the Vietnamese-language edition of Wikipedia, a free, publicly editable, online encyclopedia supported by the Wikimedia Foundation. Like the rest of Wikipedia, its content is created and accessed using the MediaWiki wiki software.
The reliability of Wikipedia and its user-generated editing model, particularly its English-language edition, has been questioned and tested. Wikipedia is written and edited by volunteer editors, who generate online content with the editorial oversight of other volunteer editors via community-generated policies and guidelines. The reliability of the project has been tested statistically through comparative review, analysis of the historical patterns, and strengths and weaknesses inherent in its editing process. The online encyclopedia has been criticized for its factual unreliability, principally regarding its content, presentation, and editorial processes. Studies and surveys attempting to gauge the reliability of Wikipedia have mixed results. Wikipedia's reliability was frequently criticized in the 2000s but has been improved; its English-language edition has been generally praised in the late 2010s and early 2020s.
Citizendium is an English-language wiki-based free online encyclopedia launched by Larry Sanger, co-founder of Nupedia and Wikipedia.
WikiPilipinas is an online, free content website which bills itself as a combination "non-academic encyclopedia", web portal, directory and almanac for Philippine-based knowledge. Like Wikipedia, it contains various articles on Philippine-related topics. Unlike Wikipedia, many of the articles cover topics that would otherwise be deemed unencyclopedic by the stricter Wikipedia. The service for example, promotes the concept of original research and eschews the larger encyclopedia's neutral point-of-view principle.
Uncyclopedia is the name of several forks of satirical online encyclopedias that parody Wikipedia. Its logo, a hollow "puzzle potato", parodies Wikipedia's globe puzzle logo, and it styles itself as "the content-free encyclopedia", parodying Wikipedia's slogan of "the free encyclopedia" and likely as a play the fact that Wikipedia is described as a "free-content" encyclopedia. Founded in 2005 as an English-language wiki, the project spans more than 75 languages as well as several subprojects parodying other wikis. Uncyclopedia's name is a portmanteau of the prefix un- and the word encyclopedia.
Radiopaedia is a wiki-based international collaborative educational web resource containing a radiology encyclopedia and imaging case repository. It is currently the largest freely available radiology related resource in the world with more than 50,000 patient cases and over 16,000 reference articles on radiology-related topics. The open edit nature of articles allows radiologists, radiology trainees, radiographers, sonographers, and other healthcare professionals interested in medical imaging to refine most content through time. An editorial board peer reviews all contributions.
WikiTrust was a software product, available as a Firefox Plugin, which aimed to assist editors in detecting vandalism and dubious edits by highlighting the "untrustworthy" text with a yellow or orange background. As of September 2017, the server is offline, but the code is still available for download.
Nupedia was an English-language online encyclopedia whose articles were written by volunteer contributors with relevant subject matter expertise, reviewed by expert editors before publication, and licensed as free content. It was founded by Jimmy Wales and underwritten by Bomis, with Larry Sanger as editor-in-chief. Nupedia operated from October 1999 until September 2003. It is best known today as the predecessor of Wikipedia. Nupedia had a seven-step approval process to control content of articles before being posted, rather than live wiki-based updating. Nupedia was designed by a committee of experts who predefined the rules. It had only 21 articles in its first year, compared with Wikipedia having 200 articles in the first month, and 18,000 in the first year.
The following outline is provided as an overview of and a topical guide to Wikipedia:
PlanetPhysics was a virtual community with several Internet sites supported by a non-profit organization registered in the USA in an open science, open data, peer-to-peer review mode that aimed to help make physics, and related mathematics, knowledge much more accessible, as well as to further develop physical, logical, computational and mathematical physics concepts.
Gender bias on Wikipedia includes various gender-related disparities on Wikipedia, particularly the overrepresentation of men among both volunteer contributors and article subjects, as well as lesser coverage of and topics primarily of interest to women.
