Wikipedia has also spawned several sister projects, which are also wikis run by the Wikimedia Foundation. These other Wikimedia projects include Wiktionary, a dictionary project launched in December 2002, Wikiquote, a collection of quotations created a week after Wikimedia launched, Wikibooks, a collection of collaboratively written free textbooks and annotated texts, Wikimedia Commons, a site devoted to free-knowledge multimedia, Wikinews, for citizen journalism, and Wikiversity, a project for the creation of free learning materials and the provision of online learning activities. Another sister project of Wikipedia, Wikispecies, is a catalogue of species. In 2012 Wikivoyage, an editable travel guide, and Wikidata, an editable knowledge base, launched.
Following the departure of Tretikov from Wikipedia due to issues concerning the use of the "superprotection" feature which some language versions of Wikipedia have adopted, Katherine Maher became the third executive director the Wikimedia Foundation in June 2016. Maher has stated that one of her priorities would be the issue of editor harassment endemic to Wikipedia as identified by the Wikipedia board in December. Maher stated regarding the harassment issue that: "It establishes a sense within the community that this is a priority ... (and that correction requires that) it has to be more than words."
More InfoThe operation of Wikipedia depends on MediaWiki, a custom-made, free and open source wiki software platform written in PHP and built upon the MySQL database system. The software incorporates programming features such as a macro language, variables, a transclusion system for templates, and URL redirection. MediaWiki is licensed under the GNU General Public License and it is used by all Wikimedia projects, as well as many other wiki projects. Originally, Wikipedia ran on UseModWiki written in Perl by Clifford Adams (Phase I), which initially required CamelCase for article hyperlinks; the present double bracket style was incorporated later. Starting in January 2002 (Phase II), Wikipedia began running on a PHP wiki engine with a MySQL database; this software was custom-made for Wikipedia by Magnus Manske. The Phase II software was repeatedly modified to accommodate the exponentially increasing demand. In July 2002 (Phase III), Wikipedia shifted to the third-generation software, MediaWiki, originally written by Lee Daniel Crocker.
More InfoIn addition to logistic growth in the number of its articles, Wikipedia has steadily gained status as a general reference website since its inception in 2001. About 50 percent of search engine traffic to Wikipedia comes from Google, a good portion of which is related to academic research. The number of readers of Wikipedia worldwide reached 365 million at the end of 2009. The Pew Internet and American Life project found that one third of US Internet users consulted Wikipedia. In 2011 Business Insider gave Wikipedia a valuation of $4 billion if it ran advertisements.
More InfoWikipedia receives between 25,000 and 60,000 page requests per second, depending on time of day. As of 2019, page requests are first passed to a front-end layer of Varnish caching servers. Further statistics, based on a publicly available 3-month Wikipedia access trace, are available. Requests that cannot be served from the Varnish cache are sent to load-balancing servers running the Linux Virtual Server software, which in turn pass them to one of the Apache web servers for page rendering from the database. The web servers deliver pages as requested, performing page rendering for all the language editions of Wikipedia. To increase speed further, rendered pages are cached in a distributed memory cache until invalidated, allowing page rendering to be skipped entirely for most common page accesses.
More InfoArticles for traditional encyclopedias such as Encyclopædia Britannica are carefully and deliberately written by experts, lending such encyclopedias a reputation for accuracy. However, a peer review in 2005 of forty-two scientific entries on both Wikipedia and Encyclopædia Britannica by the science journal Nature found few differences in accuracy, and concluded that "the average science entry in Wikipedia contained around four inaccuracies; Britannica, about three." Reagle suggested that while the study reflects "a topical strength of Wikipedia contributors" in science articles, "Wikipedia may not have fared so well using a random sampling of articles or on humanities subjects." Others raised similar critiques. The findings by Nature were disputed by Encyclopædia Britannica, and in response, Nature gave a rebuttal of the points raised by Britannica. In addition to the point-for-point disagreement between these two parties, others have examined the sample size and selection method used in the Nature effort, and suggested a "flawed study design" (in Nature's manual selection of articles, in part or in whole, for comparison), absence of statistical analysis (e.g., of reported confidence intervals), and a lack of study "statistical power" (i.e., owing to small sample size, 42 or 4 × 101 articles compared, vs >105 and >106 set sizes for Britannica and the English Wikipedia, respectively).
More InfoWe don't show ads. Help us keep it that way.