Wikipedia

This article is about the Internet encyclopedia. For otheruses, see Wikipedia (disambiguation).For Wikipedias non-encyclopedic visitor introduction,see Wikipedia:About.

Wikipedia ( i/wkpidi/ or i/wkipidi/ WIK-i-PEE-dee-) is a free-access, free-content Internet en-cyclopedia, supported and hosted by the non-profitWikimedia Foundation. Those who can access the sitecan edit most of its articles, with the expectation thatthey follow the websites policies.[6] Wikipedia is rankedamong the ten most popular websites[5] and constitutesthe Internet's largest and most popular general referencework.[7][8][9]

Jimmy Wales and Larry Sanger launched Wikipedia onJanuary 15, 2001. Sanger[10] coined its name,[11] aportmanteau of wiki[notes 2] and encyclopedia. Initiallyonly in English, Wikipedia quickly became multilingualas it developed similar versions in other languages, whichdiffer in content and in editing practices. The EnglishWikipedia is now one of more than 200 Wikipedias andis the largest with over 4.9 million articles. There is agrand total, including all Wikipedias, of nearly 35 mil-lion articles in 288 different languages.[13] As of Febru-ary 2014, it had 18 billion page views and nearly 500 mil-lion unique visitors each month.[14] Globally, Wikipediahad more than 19 million accounts,[15] out of which therewere about 69,000 active editors as of November 2014.[2]

Supporters of Wikipedia cite a 2005 survey of Wikipediapublished in Nature based on a comparison of 42 sciencearticles with Encyclopdia Britannica, which found thatWikipedias level of accuracy approached Encyclop-dia Britannica ' s.[16] Criticisms of Wikipedia includeclaims that it exhibits systemic bias, presents a mixtureof truths, half truths, and some falsehoods,[17] and issubject to manipulation and spin.[18]

1 Openness

Unlike traditional encyclopedias, Wikipedia follows theprocrastination principle[notes 3] regarding the security ofits content.[19] It started almost entirely openanyonecould create articles, and any Wikipedia article couldbe edited by any reader, even those who did not have aWikipedia account. Modifications to all articles would bepublished immediately. As a result, any article could con-tain inaccuracies such as errors, ideological biases, and

Differences between versions of an article are highlighted asshown.

nonsensical or irrelevant text.

1.1 Restrictions

Over time, the English Wikipedia and some otherWikipedias gradually have restricted modifications. Forexample, in the English Wikipedia and some otherlanguage editions, only registered users may create anew article.[20] On the English Wikipedia and someothers, some particularly controversial, sensitive and/orvandalism-prone pages are now "protected" to somedegree.[21] A frequently vandalized article can be semi-protected, meaning that only certain editors are ableto modify it.[22] A particularly contentious article maybe locked so that only administrators are able to makechanges.[23]

In certain cases, all editors are allowed to submit mod-ifications, but review is required for some editors, de-pending on certain conditions. For example, the GermanWikipedia maintains stable versions of articles,[24]which have passed certain reviews. Following protractedtrials and community discussion, the English Wikipediaintroduced the pending changes system in December2012.[25] Under this system, new users edits to cer-tain controversial or vandalism-prone articles are sub-ject to review from an established Wikipedia editor be-fore publication.[26]

1.2 Review of changes

Although changes are not systematically reviewed, thesoftware that powers Wikipedia provides certain toolsallowing anyone to review changes made by others.

1

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2 2 POLICIES AND LAWS

The editing interface of Wikipedia

The History page of each article links to eachrevision.[notes 4][27] On most articles, anyone can undo oth-ers changes by clicking a link on the articles history page.Anyone can view the latest changes to articles, and any-one may maintain a watchlist of articles that interestthem so they can be notified of any changes. New pagespatrol is a process whereby newly created articles arechecked for obvious problems.[28]

In 2003, economics PhD student Andrea Ciffolilli ar-gued that the low transaction costs of participating in awiki create a catalyst for collaborative development, andthat features such as allowing easy access to past ver-sions of a page favor creative construction over cre-ative destruction.[29]

1.3 Vandalism

Main article: Vandalism on Wikipedia

Any edit that changes content in a way that deliberatelycompromises the integrity of Wikipedia is consideredvandalism. The most common and obvious types ofvandalism include insertion of obscenities and crude hu-mor. Vandalism can also include advertising languageand other types of spam.[30] Sometimes editors commitvandalism by removing information or entirely blanking agiven page. Less common types of vandalism, such as thedeliberate addition of plausible but false information to anarticle, can be more difficult to detect. Vandals can intro-duce irrelevant formatting, modify page semantics suchas the pages title or categorization, manipulate the un-derlying code of an article, or use images disruptively.[31]

Obvious vandalism is generally easy to remove from wikiarticles; the median time to detect and fix vandalism is afew minutes.[32][33] However, some vandalism takes muchlonger to repair.[34]

In the Wikipedia Seigenthaler biography incident, ananonymous editor introduced false information into thebiography of American political figure John Seigenthalerin May 2005. Seigenthaler was falsely presented as a sus-pect in the assassination of John F. Kennedy.[34] The ar-ticle remained uncorrected for four months.[34] Seigen-thaler, the founding editorial director of USA Today andfounder of the Freedom Forum First Amendment Cen-

American journalist John Seigenthaler (19272014), subject ofthe Seigenthaler incident

ter at Vanderbilt University, called Wikipedia co-founderJimmy Wales and asked whether he had any way of know-ing who contributed the misinformation. Wales repliedthat he did not, although the perpetrator was eventu-ally traced.[35][36] After the incident, Seigenthaler de-scribed Wikipedia as a flawed and irresponsible researchtool.[34] This incident led to policy changes at Wikipedia,specifically targeted at tightening up the verifiability ofbiographical articles of living people.[37]

2 Policies and lawsSee also: Wikipedia:Five Pillars

Content in Wikipedia is subject to the laws (in particular,copyright laws) of the United States and of the U.S. stateof Virginia, where the majority of Wikipedias serversare located. Beyond legal matters, the editorial princi-ples of Wikipedia are embodied in the five pillars andin numerous policies and guidelines intended to appro-priately shape content. Even these rules are stored inwiki form, and Wikipedia editors write and revise thewebsites policies and guidelines.[38] Editors can enforcethese rules by deleting or modifying non-compliant ma-terial. Originally, rules on the non-English editions ofWikipedia were based on a translation of the rules forthe English Wikipedia. They have since diverged to someextent.[24]

2.1 Content policies and guidelines

Main pages: Wikipedia:Content policies andWikipedia:Content guidelines

According to the rules on the English Wikipedia, eachentry in Wikipedia must be about a topic that isencyclopedic and is not a dictionary entry or dictionary-like.[39] A topic should also meet Wikipedias standards

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3

of notability,[40] which generally means that the topicmust have been covered in mainstream media or majoracademic journal sources that are independent of the ar-ticles subject. Further, Wikipedia intends to convey onlyknowledge that is already established and recognized.[41]It must not present original research. A claim that is likelyto be challenged requires a reference to a reliable source.Among Wikipedia editors, this is often phrased as veri-fiability, not truth to express the idea that the readers, notthe encyclopedia, are ultimately responsible for check-ing the truthfulness of the articles and making their owninterpretations.[42] This can at times lead to the removal ofinformation that is valid.[43] Finally, Wikipedia must nottake sides.[44] All opinions and viewpoints, if attributableto external sources, must enjoy an appropriate share ofcoverage within an article.[45] This is known as neutralpoint of view (NPOV).

3 Governance

Wikipedias initial anarchy integrated democratic and hi-erarchical elements over time.[46][47] A small number ofadministrators are allowed to modify any article, and aneven smaller number of bureaucrats can name new ad-ministrators.An article is not considered to be owned by its creatoror any other editor and is not vetted by any recognizedauthority.[48]

Avoidance of a tragedy of the commons is attempted withthe attention of individual Wikipedians.[49]

3.1 Administrators

Editors in good standing in the community can run forone of many levels of volunteer stewardship: this be-gins with "administrator",[50][51] privileged users who candelete pages, prevent articles from being changed in caseof vandalism or editorial disputes, and try to prevent cer-tain persons from editing. Despite the name, adminis-trators are not supposed to enjoy any special privilege indecision-making; instead, their powers are mostly limitedto making edits that have project-wide effects and thusare disallowed to ordinary editors, and to implement re-strictions intended to prevent certain persons from mak-ing disruptive edits (such as vandalism).[52][53]

Fewer editors become administrators than in years past,in part because the process of vetting potential Wikipediaadministrators has become more rigorous.[54]

3.2 Dispute resolution

Wikipedians may dispute, for example by repeatedlymaking opposite changes to an article.[55][56][57] Over

time, Wikipedia has developed documentation for edi-tors about dispute resolution. In order to determine com-munity consensus, editors can raise issues at the VillagePump, or initiate a request for comment.

3.2.1 Arbitration Committee

Main article: Arbitration Committee

The Arbitration Committee presides over the ultimatedispute resolution process. Although disputes usuallyarise from a disagreement between two opposing viewson how an article should read, the Arbitration Committeeexplicitly refuses to directly rule on the specific view thatshould be adopted. Statistical analyses suggest that thecommittee ignores the content of disputes and rather fo-cuses on the way disputes are conducted,[58] functioningnot so much to resolve disputes and make peace betweenconflicting editors, but to weed out problematic editorswhile allowing potentially productive editors back in toparticipate. Therefore, the committee does not dictatethe content of articles, although it sometimes condemnscontent changes when it deems the new content violatesWikipedia policies (for example, if the new content isconsidered biased). Its remedies include cautions andprobations (used in 63% of cases) and banning editorsfrom articles (43%), subject matters (23%) or Wikipedia(16%). Complete bans from Wikipedia are generally lim-ited to instances of impersonation and anti-social behav-ior. When conduct is not impersonation or anti-social,but rather anti-consensus or in violation of editing poli-cies, remedies tend to be limited to warnings.[59]

4 Community

Main article: Wikipedia communityEach article and each user of Wikipedia has an asso-

Video of the 2005Wikimania (an annual conference for users ofWikipedia and other projects operated by the Wikimedia Foun-dation)

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4 4 COMMUNITY

ciated Talk page. These form the primary commu-nication channel for editors to discuss, coordinate anddebate.[60]

Wikipedians and British Museum curators collaborate on the ar-ticle Hoxne Hoard in June 2010.

Wikipedias community has been described as cult-like,[61] although not always with entirely negativeconnotations.[62] The projects preference for cohesive-ness, even if it requires compromise that includes dis-regard of credentials, has been referred to as "anti-elitism".[63]

Wikipedians sometimes award one another virtual barn-stars for good work. These personalized tokens of appre-ciation reveal a wide range of valued work extending farbeyond simple editing to include social support, adminis-trative actions, and types of articulation work.[64]

Wikipedia does not require that its editors and contribu-tors provide identification.[65] As Wikipedia grew, Whowrites Wikipedia?" became one of the questions fre-quently asked on the project.[66] Jimmy Wales once ar-gued that only a community ... a dedicated group of afew hundred volunteers makes the bulk of contributionsto Wikipedia and that the project is therefore much likeany traditional organization.[67] In 2008, a Slate maga-zine article reported that: According to researchers inPalo Alto, 1 percent of Wikipedia users are responsiblefor about half of the sites edits.[68] This method of eval-uating contributions was later disputed by Aaron Swartz,who noted that several articles he sampled had large por-tions of their content (measured by number of characters)contributed by users with low edit counts.[69]

A report in August 2014 showed that Wikipedia had atleast 80,000 editors.[70] A significant decline in the num-ber of English-language editors was reported in 2013by Tom Simonite who stated: The number of activeeditors on the English-language Wikipedia peaked in2007 at more than 51,000 and has been declining eversince...(t)his past summer (2013) only 31,000 peoplecould be considered active editors.[71] Several attemptsto explain this have been offered. One possible expla-nation is that some users become turned off by theirexperiences.[72] Another explanation, according to EricGoldman, is found in editors who fail to comply with

Historical chart of the number of Wikipedians considered as ac-tive by the Wikimedia Foundation

Wikipedia cultural rituals, such as signing talk pages, im-plicitly signal that they are Wikipedia outsiders, increas-ing the odds that Wikipedia insiders may target or dis-count their contributions. Becoming a Wikipedia insiderinvolves non-trivial costs: the contributor is expected tobuild a user page, learn Wikipedia-specific technologicalcodes, submit to a sometimes convoluted dispute resolu-tion process, and learn a baffling culture rich with in-jokes and insider references. Editors who do not log inare in some sense second-class citizens on Wikipedia,[73]as participants are accredited by members of the wikicommunity, who have a vested interest in preserving thequality of the work product, on the basis of their ongo-ing participation,[74] but the contribution histories of IPaddresses cannot be attributed to a particular editor withcertainty.A 2007 study by researchers from Dartmouth Collegefound that anonymous and infrequent contributors toWikipedia [...] are as reliable a source of knowledge asthose contributors who register with the site.[75] JimmyWales stated in 2009 that "(I)t turns out over 50% of allthe edits are done by just .7% of the users... 524 people...And in fact the most active 2%, which is 1400 people,have done 73.4% of all the edits.[67] However, BusinessInsider editor and journalist Henry Blodget showed in2009 that in a random sample of articles, most contentin Wikipedia (measured by the amount of contributedtext that survives to the latest sampled edit) is created byoutsiders, while most editing and formatting is done byinsiders.[67]

A 2008 study found that Wikipedians were less agreeable,open, and conscientious than others.[76][77] According to a2009 study, there is evidence of growing resistance fromthe Wikipedia community to new content.[78]

4.1 Diversity

One study found that the contributor base to Wikipediawas barely 13% women; the average age of a contributorwas in the mid-20s.[79] A 2011 study by researchers fromthe University of Minnesota found that females com-

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5

Wikipedia editor demographics (April 2009).

prised 16.1% of the 38,497 editors who started editingWikipedia during 2009.[80] In a January 2011 New YorkTimes article, Noam Cohen observed that just 13% ofWikipedias contributors are female according to a 2009Wikimedia Foundation survey.[81] Sue Gardner, a formerexecutive director of the Wikimedia Foundation, hopedto see female contributions increase to twenty-five per-cent by 2015.[82] Linda Basch, president of the NationalCouncil for Research on Women, noted the contrast inthese Wikipedia editor statistics with the percentage ofwomen currently completing bachelors degrees, mastersdegrees and PhD programs in the United States (all atrates of 50 percent or greater).[83]

In response, various universities have hosted edit-a-thonsto encourage more women to participate in the Wikipediacommunity. In fall 2013, 15 colleges and universities, in-cluding Yale, Brown, and Pennsylvania State, offered col-lege credit for students to write feminist thinking abouttechnology into Wikipedia.[84]

In August 2014, Wikipedia co-founder Jimmy Wales an-nounced in a BBC interview the Wikimedia Foundation'splans for doubling down on the issue of gender bias onWikipedia. Wales agreed that Sue Gardners goal of 25%women enrollment by 2015 had not been met. Wales saidthe foundation would be open to more outreach, moresoftware changes,[85] and more women administrators.Software changes were left open to explore ways of in-creasing the appeal of Wikipedia to attract women read-ers to register as editors, and to increase the potentialof existing editors to nominate more women administra-tors to enhance the 'management' presence of women atWikipedia.[86]

5 Language editions

There are currently 288 language editions of Wikipedia(also called language versions, or simply Wikipedias).Twelve of these have over one million articles each

(English, Swedish, Dutch, German, French, Waray-Waray, Russian, Cebuano, Italian, Spanish, Vietnameseand Polish), three more have over 700,000 articles(Japanese, Portuguese and Chinese), 36 more haveover 100,000 articles, and 77 more have over 10,000articles.[87][88] The largest, the English Wikipedia, hasover 4.9 million articles. As of May 2015, according toAlexa, the English subdomain (en.wikipedia.org; EnglishWikipedia) receives approximately 58% of Wikipediascumulative traffic, with the remaining split among theother languages (Japanese: 8%; Spanish: 7%; German:5%; Russian: 4%).[5] As of July 2015, the six largest lan-guage editions are (in order of article count) the English,Swedish, German, Dutch, French, and Waray-WarayWikipedias.[89]

Distribution of the 35,535,898 articles in differentlanguage editions (as of 12 July 2015)[90]

English (13.8%)Swedish (5.5%)German (5.2%)Dutch (5.1%)French (4.6%)Waray-Waray (3.5%)Russian (3.5%)Cebuano (3.4%)Italian (3.4%)Spanish (3.3%)Other (48.7%)

The unit for the numbers in bars is articles. SinceWikipedia is based on the Web and therefore worldwide,contributors to the same language edition may use dif-ferent dialects or may come from different countries (asis the case for the English edition). These differencesmay lead to some conflicts over spelling differences (e.g.colour versus color)[92] or points of view.[93]

Though the various language editions are held to globalpolicies such as neutral point of view, they divergeon some points of policy and practice, most notably onwhether images that are not licensed freely may be usedunder a claim of fair use.[94][95][96]

Jimmy Wales has described Wikipedia as an effort to

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6 6 HISTORY

create and distribute a free encyclopedia of the highestpossible quality to every single person on the planet intheir own language.[97] Though each language editionfunctions more or less independently, some efforts aremade to supervise them all. They are coordinated inpart by Meta-Wiki, the Wikimedia Foundations wiki de-voted to maintaining all of its projects (Wikipedia andothers).[98] For instance, Meta-Wiki provides importantstatistics on all language editions of Wikipedia,[99] andit maintains a list of articles every Wikipedia shouldhave.[100] The list concerns basic content by subject: bi-ography, history, geography, society, culture, science,technology, and mathematics. As for the rest, it is notrare for articles strongly related to a particular languagenot to have counterparts in another edition. For example,articles about small towns in the United States might onlybe available in English, even when they meet notabilitycriteria of other language Wikipedia projects.

South America

Portugal

SouthernAfrica

pt

35%5%

60% heIsrael

Europe

NorthAmerica

70% 10%

20%

EastChinaWestChina

Europe

NorthAmerica

zh40%

45%

10%

5% West-NorthAfricaMiddleEast

Mid-NorthAfrica

NorthAmerica

ar

40%

25%

25%

10%

North America

Europe

51%

7%

42%

en

Far East,Australia

Far East,Australia

Europe

smp25%

20%

55%

North America Central Africa,Madagascar

fr

10%

5%

85%

France, WestAfrica

North America

South America

CentralAmerica

es

30%

45%

25%Spain

Europe

NorthAmerica

fa

45%

30% 25% Iran

Estimation of contributions shares from different regions in theworld to different Wikipedia editions

Translated articles represent only a small portion of ar-ticles in most editions, in part because fully automatedtranslation of articles is disallowed.[101] Articles availablein more than one language may offer "interwiki links",which link to the counterpart articles in other editions.A study published by PLOS ONE in 2012 also esti-mated the share of contributions to different editions ofWikipedia from different regions of the world. It re-ported that the proportion of the edits made from NorthAmerica was 51% for the English Wikipedia, and 25%for the simple English Wikipedia.[102] The WikimediaFoundation hopes to increase the number of editors inthe Global South to thirty-seven percent by 2015.[103]

On March 1, 2014, The Economist in an article titled TheFuture of Wikipedia cited a trend analysis concerningdata published by Wikimedia stating that: The numberof editors for the English-language version has fallen bya third in seven years.[104] The attrition rate for activeeditors in English Wikipedia was cited by The Economistas substantially in contrast to statistics for Wikipedia inother languages (non-English Wikipedia). The Economistreported that the number of contributors with an averageof five of more edits per month was relatively constantsince 2008 for Wikipedia in other languages at approx-

imately 42,000 editors within narrow seasonal variancesof about 2,000 editors up or down. The attrition rates foreditors in English Wikipedia, by sharp comparison, werecited as peaking in 2007 at approximately 50,000 editorswhich has dropped to 30,000 editors as of the start of2014. At the quoted trend rate, the number of active edi-tors in English Wikipedia has lost approximately 20,000editors to attrition since 2007, and the documented trendrate indicates the loss of another 20,000 editors by 2021,down to 10,000 active editors on English Wikipedia by2021 if left unabated.[104] Given that the trend analysispublished in The Economist presents the number of activeeditors for Wikipedia in other languages (non-EnglishWikipedia) as remaining relatively constant and success-ful in sustaining its numbers at approximately 42,000 ac-tive editors, the contrast has pointed to the effectivenessof Wikipedia in other languages to retain its active ed-itors on a renewable and sustained basis.[104] No com-ment was made concerning which of the differentiatededit policy standards from Wikipedia in other languages(non-English Wikipedia) would provide a possible alter-native to English Wikipedia for effectively amelioratingsubstantial editor attrition rates on the English languageWikipedia.[105]

6 History

Main article: History of Wikipedia

Jimmy Wales and Larry SangerOther collaborative online encyclopedias were attemptedbefore Wikipedia but none were so successful.[106]

Wikipedia began as a complementary project forNupedia, a free online English-language encyclopediaproject whose articles were written by experts and re-viewed under a formal process. Nupedia was foundedon March 9, 2000, under the ownership of Bomis, aweb portal company. Its main figures were the Bomis

https://en.wikipedia.org/wiki/Interwiki_linkshttps://en.wikipedia.org/wiki/PLOS_ONEhttps://en.wikipedia.org/wiki/North_Americahttps://en.wikipedia.org/wiki/North_Americahttps://en.wikipedia.org/wiki/English_Wikipediahttps://en.wikipedia.org/wiki/Simple_English_Wikipediahttps://en.wikipedia.org/wiki/History_of_Wikipediahttps://en.wikipedia.org/wiki/Nupediahttps://en.wikipedia.org/wiki/English_languagehttps://en.wikipedia.org/wiki/Bomishttps://en.wikipedia.org/wiki/Web_portal

7

Wikipedia originally developed from another encyclopediaproject, Nupedia.

CEO Jimmy Wales and Larry Sanger, editor-in-chief forNupedia and later Wikipedia. Nupedia was licensedinitially under its own Nupedia Open Content License,switching to the GNU Free Documentation License be-fore Wikipedias founding at the urging of Richard Stall-man.[107] Sanger and Wales founded Wikipedia.[108][109]While Wales is credited with defining the goal of mak-ing a publicly editable encyclopedia,[110][111] Sanger iscredited with the strategy of using a wiki to reach thatgoal.[112] On January 10, 2001, Sanger proposed on theNupedia mailing list to create a wiki as a feeder projectfor Nupedia.[113]

Wikipedia was formally launched on January 15, 2001,as a single English-language edition at www.wikipedia.com,[114] and announced by Sanger on the Nupediamailing list.[110] Wikipedias policy of neutral point-of-view[115] was codified in its first months. Otherwise,there were relatively few rules initially and Wikipedia op-erated independently of Nupedia.[110] Originally, Bomisintended to make Wikipedia a business for profit.[116]

Wikipedia gained early contributors from Nupedia,Slashdot postings, and web search engine indexing. ByAugust 8, 2001, Wikipedia had over 8,000 articles.[117]On September 25, 2001, Wikipedia had over 13,000articles.[118] And by the end of 2001 it had grown to ap-proximately 20,000 articles and 18 language editions. Ithad reached 26 language editions by late 2002, 46 by theend of 2003, and 161 by the final days of 2004.[119] Nu-pedia and Wikipedia coexisted until the formers serverswere taken down permanently in 2003, and its text wasincorporated into Wikipedia. English Wikipedia passedthe mark of two million articles on September 9, 2007,making it the largest encyclopedia ever assembled, sur-passing even the 1408 Yongle Encyclopedia, which hadheld the record for 600 years.[120]

Citing fears of commercial advertising and lack of con-trol in Wikipedia, users of the Spanish Wikipedia forkedfrom Wikipedia to create theEnciclopedia Libre in Febru-ary 2002.[121] These moves encouraged Wales to an-nounce that Wikipedia would not display advertisements,and to change Wikipedias domain from wikipedia.com towikipedia.org.[122]

Though the English Wikipedia reached three million ar-ticles in August 2009, the growth of the edition, in termsof the numbers of articles and of contributors, appearsto have peaked around early 2007.[123] Around 1,800articles were added daily to the encyclopedia in 2006;by 2013 that average was roughly 800.[124] A team at

the Palo Alto Research Center attributed this slowing ofgrowth to the projects increasing exclusivity and resis-tance to change.[125] Others suggest that the growth is flat-tening naturally because articles that could be called low-hanging fruittopics that clearly merit an articlehavealready been created and built up extensively.[126][127][128]

In November 2009, a researcher at the Rey Juan Car-los University in Madrid (Spain) found that the EnglishWikipedia had lost 49,000 editors during the first threemonths of 2009; in comparison, the project lost only4,900 editors during the same period in 2008.[129][130]The Wall Street Journal cited the array of rules appliedto editing and disputes related to such content among thereasons for this trend.[131] Wales disputed these claims in2009, denying the decline and questioning the methodol-ogy of the study.[132] Two years later, Wales acknowl-edged the presence of a slight decline, noting a de-crease from a little more than 36,000 writers in June2010 to 35,800 in June 2011.[133] In the same interview,Wales also claimed the number of editors was stableand sustainable, a claim which was questioned by MITsTechnology Review in a 2013 article titled The Declineof Wikipedia.[71] In July 2012, the Atlantic reported thatthe number of administrators is also in decline.[134] Inthe November 25, 2013, issue of New York magazine,Katherine Ward stated Wikipedia, the sixth-most-usedwebsite, is facing an internal crisis. In 2013, MITs Tech-nology Review revealed that since 2007, the site has losta third of the volunteer editors who update and correctthe online encyclopedias millions of pages and those stillthere have focused increasingly on minutiae.[135]

Wikipedia blackout protest against SOPA on January 18, 2012

A promotional video of the Wikimedia Foundation that en-courages viewers to edit Wikipedia, mostly reviewing 2014 viaWikipedia content

https://en.wikipedia.org/wiki/Nupediahttps://en.wikipedia.org/wiki/Jimmy_Waleshttps://en.wikipedia.org/wiki/Larry_Sangerhttps://en.wikipedia.org/wiki/Editinghttps://en.wikipedia.org/wiki/Open_Contenthttps://en.wikipedia.org/wiki/GNU_Free_Documentation_Licensehttps://en.wikipedia.org/wiki/Richard_Stallmanhttps://en.wikipedia.org/wiki/Richard_Stallmanhttps://en.wikipedia.org/wiki/Wikihttps://en.wikipedia.org/wiki/Electronic_mailing_listhttps://en.wikipedia.org/wiki/Slashdothttps://en.wikipedia.org/wiki/Web_search_enginehttps://en.wikipedia.org/wiki/English_Wikipediahttps://en.wikipedia.org/wiki/Yongle_Encyclopediahttps://en.wikipedia.org/wiki/Spanish_Wikipediahttps://en.wikipedia.org/wiki/Fork_(software_development)https://en.wikipedia.org/wiki/Enciclopedia_Libre_Universal_en_Espa%C3%B1olhttps://en.wikipedia.org/wiki/Palo_Alto_Research_Centerhttps://en.wiktionary.org/wiki/low-hanging%2520fruithttps://en.wiktionary.org/wiki/low-hanging%2520fruithttps://en.wikipedia.org/wiki/Rey_Juan_Carlos_Universityhttps://en.wikipedia.org/wiki/Rey_Juan_Carlos_Universityhttps://en.wikipedia.org/wiki/Madridhttps://en.wikipedia.org/wiki/Spainhttps://en.wikipedia.org/wiki/Technology_Reviewhttps://en.wikipedia.org/wiki/The_Atlantichttps://en.wikipedia.org/wiki/New_York_(magazine)https://en.wikipedia.org/wiki/Stop_Online_Piracy_Act

8 7 CRITICAL RECEPTION

In January 2007, Wikipedia entered for the first time thetop-ten list of the most popular websites in the UnitedStates, according to comScore Networks. With 42.9 mil-lion unique visitors, Wikipedia was ranked number 9,surpassing the New York Times (#10) and Apple (#11).This marked a significant increase over January 2006,when the rank was number 33, with Wikipedia receiv-ing around 18.3 million unique visitors.[136] As of March2015, Wikipedia has rank 6[5][137] among websites interms of popularity according to Alexa Internet. In2014, it received 8 billion pageviews every month.[138]On February 9, 2014, The New York Times reported thatWikipedia has 18 billion page views and nearly 500 mil-lion unique visitors a month, according to the ratingsfirm comScore.[14]

On January 18, 2012, the English Wikipedia participatedin a series of coordinated protests against two proposedlaws in the United States Congressthe Stop OnlinePiracy Act (SOPA) and the PROTECT IP Act (PIPA)by blacking out its pages for 24 hours.[139] More than 162million people viewed the blackout explanation page thattemporarily replaced Wikipedia content.[140][141]

Loveland and Reagle argue that, in process, Wikipediafollows a long tradition of historical encyclopediasthat accumulated improvements piecemeal through"stigmergic accumulation.[142][143]

On January 20, 2014, Subodh Varma reporting for TheEconomic Times indicated that not only had Wikipediagrowth flattened but that it has lost nearly 10 per cent ofits page-views last year. Thats a decline of about 2 bil-lion between December 2012 and December 2013. Itsmost popular versions are leading the slide: page-viewsof the English Wikipedia declined by 12 per cent, thoseof German version slid by 17 per cent and the Japaneseversion lost 9 per cent.[144] Varma added that, WhileWikipedias managers think that this could be due to er-rors in counting, other experts feel that Googles Knowl-edge Graphs project launched last year may be gobblingup Wikipedia users.[144] When contacted on this matter,Clay Shirky, associate professor at New York Universityand fellow at Harvards Berkman Center for internet andSecurity indicated that he suspected much of the pageview decline was due to Knowledge Graphs, stating, Ifyou can get your question answered from the search page,you don't need to click [any further].[144]

7 Critical reception

See also: Academic studies about Wikipedia andCriticism of Wikipedia

Some sites have been developed to criticize some ofWikipedias aspects, like the issue of paid editing ofWikipedia,[145] a service formerly offered by the Wiki-PR company, which claimed it could have clients pages

edited "...using our network of established Wikipedia ed-itors and admins.[146]

Several Wikipedians have criticized Wikipedias largeand growing regulation, which includes over 50 policiesand nearly 150,000 words as of 2014.[147][148]

Critics have stated that Wikipedia exhibits systemicbias. Columnist and journalist Edwin Black criticizesWikipedia for being a mixture of truth, half truth, andsome falsehoods.[17] Articles in The Chronicle of HigherEducation and The Journal of Academic Librarianshiphave criticized Wikipedias Undue Weight policy, con-cluding that the fact that Wikipedia explicitly is not de-signed to provide correct information about a subject, butrather only present the majority weight of viewpoints,creates omissions which can lead to false beliefs based onincomplete information.[149][150][151]

Journalists Oliver Kamm and Edwin Black noted howarticles are dominated by the loudest and most persis-tent voices, usually by a group with an ax to grindon the topic.[17][152] An article in Education Next Jour-nal concluded that as a resource about controversial top-ics, Wikipedia is notoriously subject to manipulation andspin.[18]

In 2006, the Wikipedia Watch criticism website listeddozens of examples of plagiarism in the EnglishWikipedia.[153]

7.1 Accuracy of content

Main article: Reliability of Wikipedia

Articles for traditional encyclopedias such asEncyclopdia Britannica are carefully and deliber-ately written by experts, lending such encyclopedias areputation for accuracy. Conversely, Wikipedia is oftencited for factual inaccuracies and misrepresentations.However, a peer review in 2005 of forty-two scientificentries on both Wikipedia and Encyclopdia Britannicaby the science journal Nature found few differencesin accuracy, and concluded that the average scienceentry in Wikipedia contained around four inaccuracies;Britannica, about three.[16] Reagle suggested that whilethe study reflects a topical strength of Wikipediacontributors in science articles, Wikipedia may nothave fared so well using a random sampling of articlesor on humanities subjects.[154] The findings by Naturewere disputed by Encyclopdia Britannica,[155][156] andin response, Nature gave a rebuttal of the points raisedby Britannica.[157] In addition to the point-for-pointdisagreement between these two parties, others haveexamined the sample size and selection method used inthe Nature effort, and suggested a flawed study design(in Nature ' s manual selection of articles, in part or inwhole, for comparison), absence of statistical analysis(e.g., of reported confidence intervals), and a lack of

https://en.wikipedia.org/wiki/ComScorehttps://en.wikipedia.org/wiki/New_York_Timeshttps://en.wikipedia.org/wiki/Apple_Inc.https://en.wikipedia.org/wiki/Alexa_Internethttps://en.wikipedia.org/wiki/Page_viewhttps://en.wikipedia.org/wiki/Unique_visitorhttps://en.wikipedia.org/wiki/Stop_Online_Piracy_Acthttps://en.wikipedia.org/wiki/Stop_Online_Piracy_Acthttps://en.wikipedia.org/wiki/PROTECT_IP_Acthttps://en.wikipedia.org/wiki/2012_Wikipedia_blackouthttps://en.wikipedia.org/wiki/Stigmergyhttps://en.wikipedia.org/wiki/Academic_studies_about_Wikipediahttps://en.wikipedia.org/wiki/Criticism_of_Wikipediahttps://en.wikipedia.org/wiki/Paid_editing_of_Wikipediahttps://en.wikipedia.org/wiki/Paid_editing_of_Wikipediahttps://en.wikipedia.org/wiki/Wiki-PRhttps://en.wikipedia.org/wiki/Wiki-PRhttps://en.wikipedia.org/wiki/Criticism_of_Wikipedia#Excessive_regulationhttps://en.wikipedia.org/wiki/Criticism_of_Wikipedia#Excessive_regulationhttps://en.wikipedia.org/wiki/Systemic_biashttps://en.wikipedia.org/wiki/Systemic_biashttps://en.wikipedia.org/wiki/Edwin_Blackhttps://en.wikipedia.org/wiki/The_Chronicle_of_Higher_Educationhttps://en.wikipedia.org/wiki/The_Chronicle_of_Higher_Educationhttps://en.wikipedia.org/wiki/The_Journal_of_Academic_Librarianshiphttps://en.wikipedia.org/wiki/Wikipedia:Unduehttps://en.wikipedia.org/wiki/Oliver_Kammhttps://en.wikipedia.org/wiki/Edwin_Blackhttps://en.wikipedia.org/wiki/Hoover_Institution#Publicationshttps://en.wikipedia.org/wiki/Spin_(public_relations)https://en.wikipedia.org/wiki/Plagiarismhttps://en.wikipedia.org/wiki/Reliability_of_Wikipediahttps://en.wikipedia.org/wiki/Encyclop%C3%A6dia_Britannicahttps://en.wikipedia.org/wiki/Confidence_interval

7.2 Quality of writing 9

study statistical power (i.e., owing to small samplesize, 42 or 4 x 101 articles compared, vs >105 and>106 set sizes for Britannica and the English Wikipedia,respectively).[158]

As a consequence of the open structure, Wikipediamakes no guarantee of validity of its content, sinceno one is ultimately responsible for any claims appear-ing in it.[159] Concerns have been raised by PC Worldin 2009 regarding the lack of accountability that re-sults from users anonymity,[160] the insertion of falseinformation,[161] vandalism, and similar problems.Economist Tyler Cowen wrote: If I had to guess whetherWikipedia or the median refereed journal article on eco-nomics was more likely to be true, after a not so long thinkI would opt for Wikipedia. He comments that some tra-ditional sources of non-fiction suffer from systemic bi-ases and novel results, in his opinion, are over-reported injournal articles and relevant information is omitted fromnews reports. However, he also cautions that errors arefrequently found on Internet sites, and that academics andexperts must be vigilant in correcting them.[162]

Critics argue that Wikipedias open nature and alack of proper sources for most of the informationmakes it unreliable.[163] Some commentators suggest thatWikipedia may be reliable, but that the reliability ofany given article is not clear.[164] Editors of traditionalreference works such as the Encyclopdia Britannicahave questioned the projects utility and status as anencyclopedia.[165]

Wikipedias open structure inherently makes it aneasy target for Internet trolls, spammers, and vari-ous forms of paid advocacy seen as counterproductiveto the maintenance of a neutral and verifiable onlineencyclopedia.[27][167] In response to paid advocacy edit-ing and undisclosed editing issues, Wikipedia was re-ported in an article by Jeff Elder in The Wall Street Jour-nal on June 16, 2014 to have strengthened its rules andlaws against undisclosed editing.[168] The article statedthat: Beginning Monday (from date of article), changesin Wikipedias terms of use will require anyone paid toedit articles to disclose that arrangement. Katherine Ma-her, the nonprofit Wikimedia Foundations chief com-munications officer, said the changes address a senti-ment among volunteer editors that, 'we're not an advertis-ing service; we're an encyclopedia.'"[168][169][170][171][172]These issues, among others, had been parodied since thefirst decade of Wikipedia, notably by Stephen Colbert onThe Colbert Report.[173]

Most university lecturers discourage students fromciting any encyclopedia in academic work, prefer-ring primary sources;[174] some specifically prohibitWikipedia citations.[175][176] Wales stresses that encyclo-pedias of any type are not usually appropriate to useas citeable sources, and should not be relied upon asauthoritative.[177] Wales once (2006 or earlier) said hereceives about ten emails weekly from students saying

they got failing grades on papers because they citedWikipedia; he told the students they got what they de-served. For Gods sake, you're in college; don't cite theencyclopedia, he said.[178]

In February 2007, an article in The Harvard Crim-son newspaper reported that a few of the professors atHarvard University include Wikipedia in their syllabi,but that there is a split in their perception of usingWikipedia.[179] In June 2007, former president of theAmerican Library Association Michael Gorman con-demned Wikipedia, along with Google,[180] stating thatacademics who endorse the use of Wikipedia are theintellectual equivalent of a dietitian who recommends asteady diet of Big Macs with everything.A Harvard law textbook, Legal Research in a Nutshell(2011), cites Wikipedia as a general source that can bea real boon in coming up to speed in the law governing asituation and, while not authoritative, can provide basicfacts as well as leads to more in-depth resources.[181]

7.1.1 Medical information

See also: Health information on Wikipedia

On March 5, 2014, Julie Beck writing for The At-lantic magazine in an article titled Doctors #1 Sourcefor Healthcare Information: Wikipedia, stated thatFifty percent of physicians look up conditions on the(Wikipedia) site, and some are editing articles themselvesto improve the quality of available information.[182]Beck continued to detail in this article new programs ofDr. Amin Azzam at the University of San Franciscoto offer medical school courses to medical students forlearning to edit and improve Wikipedia articles on health-related issues, as well as internal quality control programswithin Wikipedia organized by Dr. James Heilman toimprove a group of 200 health-related articles of centralmedical importance up to Wikipedias highest standard ofpeer review evaluated articles using its Featured Articleand Good Article peer review evaluation standards.[182]In a May 7, 2014 follow-up article in The Atlantic titledCan Wikipedia Ever Be a Definitive Medical Text?",Julie Beck quotes Wikiproject Medicines Dr. JamesHeilman as stating: Just because a reference is peer-reviewed doesn't mean its a high-quality reference.[183]Beck added that: Wikipedia has its own peer reviewprocess before articles can be classified as 'good' or 'fea-tured.' Heilman, who has participated in that process be-fore, says 'less than 1 percent' of Wikipedias medical ar-ticles have passed.[183]

7.2 Quality of writing

Because contributors usually rewrite small portions of anentry rather than making full-length revisions, high- andlow-quality content may be intermingled within an entry.

https://en.wikipedia.org/wiki/Accountabilityhttps://en.wikipedia.org/wiki/Vandalismhttps://en.wikipedia.org/wiki/Tyler_Cowenhttps://en.wikipedia.org/wiki/Reference_workhttps://en.wikipedia.org/wiki/Utilityhttps://en.wikipedia.org/wiki/Troll_(Internet)https://en.wikipedia.org/wiki/Spam_(electronic)https://en.wikipedia.org/wiki/Conflict-of-interest_editing_on_Wikipediahttps://en.wikipedia.org/wiki/Conflict-of-interest_editing_on_Wikipediahttps://en.wikipedia.org/wiki/Stephen_Colberthttps://en.wikipedia.org/wiki/The_Colbert_Reporthttps://en.wikipedia.org/wiki/Lecturerhttps://en.wikipedia.org/wiki/Academiahttps://en.wikipedia.org/wiki/Primary_sourcehttps://en.wikipedia.org/wiki/Emailhttps://en.wikipedia.org/wiki/The_Harvard_Crimsonhttps://en.wikipedia.org/wiki/The_Harvard_Crimsonhttps://en.wikipedia.org/wiki/Harvard_Universityhttps://en.wikipedia.org/wiki/Syllabushttps://en.wikipedia.org/wiki/American_Library_Associationhttps://en.wikipedia.org/wiki/Michael_Gorman_(librarian)https://en.wikipedia.org/wiki/Googlehttps://en.wikipedia.org/wiki/Health_information_on_Wikipediahttps://en.wikipedia.org/wiki/Health_information_on_Wikipediahttps://en.wikipedia.org/wiki/Health_information_on_Wikipediahttps://en.wikipedia.org/wiki/James_Heilman

10 7 CRITICAL RECEPTION

Roy Rosenzweig, a history professor, stated that Ameri-can National Biography Online outperformed Wikipediain terms of its clear and engaging prose, which, he said,was an important aspect of good historical writing.[184]Contrasting Wikipedias treatment of Abraham Lincolnto that of Civil War historian James McPherson in Amer-ican National Biography Online, he said that both wereessentially accurate and covered the major episodes inLincolns life, but praised McPhersons richer contex-tualization [...] his artful use of quotations to captureLincolns voice [...] and [...] his ability to convey aprofound message in a handful of words. By contrast,he gives an example of Wikipedias prose that he findsboth verbose and dull. Rosenzweig also criticizedthe wafflingencouraged by the npov policy[which]means that it is hard to discern any overall interpretivestance in Wikipedia history. By example, he quotedthe conclusion of Wikipedias article on William ClarkeQuantrill. While generally praising the article, he pointedout its waffling conclusion: Some historians [...] re-member him as an opportunistic, bloodthirsty outlaw,while others continue to view him as a daring soldier andlocal folk hero.[184]

Other critics have made similar charges that, even ifWikipedia articles are factually accurate, they are of-ten written in a poor, almost unreadable style. FrequentWikipedia critic Andrew Orlowski commented: Evenwhen a Wikipedia entry is 100 per cent factually correct,and those facts have been carefully chosen, it all too of-ten reads as if it has been translated from one language toanother then into to a third, passing an illiterate transla-tor at each stage.[185] A study of articles on cancer wasundertaken in 2010 by Yaacov Lawrence of the Kim-mel Cancer Center at Thomas Jefferson University lim-ited to those Wikipedia articles which could be foundin the Physician Data Query and excluding Wikipediaarticles written at the start class or the stub classlevel. Lawrence found the articles accurate but not veryreadable, and thought that Wikipedias lack of readabil-ity (to non-college readers) may reflect its varied originsand haphazard editing.[186] The Economist argued thatbetter-written articles tend to be more reliable: inele-gant or ranting prose usually reflects muddled thoughtsand incomplete information.[187]

7.3 Coverage of topics and systemic bias

See also: Notability in English Wikipedia

Wikipedia seeks to create a summary of all human knowl-edge in the form of an online encyclopedia, with eachtopic covered encyclopedically in one article. Since it hasterabytes of disk space, it can have far more topics thancan be covered by any printed encyclopedia.[188] The ex-act degree and manner of coverage on Wikipedia is underconstant review by its editors, and disagreements are notuncommon (see deletionism and inclusionism).[189][190]

Wikipedia contains materials that some people mayfind objectionable, offensive, or pornographic becauseWikipedia is not censored. The policy has sometimesproved controversial: in 2008, Wikipedia rejected an on-line petition against the inclusion of images of Muham-mad in the English edition of its Muhammad article, cit-ing this policy. The presence of politically, religiously,and pornographically sensitive materials in Wikipediahas led to the censorship of Wikipedia by national au-thorities in China,[191] Pakistan,[192] and the United King-dom,[193] among other countries.

Pie chart ofWikipedia content by subject as of January 2008[194]

A 2008 study conducted by researchers at Carnegie Mel-lon University and Palo Alto Research Center gave a dis-tribution of topics as well as growth (from July 2006 toJanuary 2008) in each field:[194]

Culture and the arts: 30% (210%)

Biographies and persons: 15% (97%)

Geography and places: 14% (52%)

Society and social sciences: 12% (83%)

History and events: 11% (143%)

Natural and physical sciences: 9% (213%)

Technology and the applied sciences: 4% (6%)

Religions and belief systems: 2% (38%)

Health: 2% (42%)

Mathematics and logic: 1% (146%)

Thought and philosophy: 1% (160%)

These numbers refer only to the quantity of articles: it ispossible for one topic to contain a large number of shortarticles and another to contain a small number of largeones. Through its "Wikipedia Loves Libraries" program,Wikipedia has partnered with major public libraries suchas the New York Public Library for the Performing Artsto expand its coverage of underrepresented subjects andarticles.[195]

https://en.wikipedia.org/wiki/Roy_Rosenzweighttps://en.wikipedia.org/wiki/Abraham_Lincolnhttps://en.wikipedia.org/wiki/American_Civil_Warhttps://en.wikipedia.org/wiki/James_M._McPhersonhttps://en.wikipedia.org/wiki/William_Clarke_Quantrillhttps://en.wikipedia.org/wiki/William_Clarke_Quantrillhttps://en.wikipedia.org/wiki/Cancerhttps://en.wikipedia.org/wiki/Thomas_Jefferson_Universityhttps://en.wikipedia.org/wiki/Notability_in_English_Wikipediahttps://en.wikipedia.org/wiki/Humanhttps://en.wikipedia.org/wiki/Terabytehttps://en.wikipedia.org/wiki/Deletionism_and_inclusionism_in_Wikipediahttps://en.wikipedia.org/wiki/Wikipedia:Wikipedia_is_not#Wikipedia_is_not_censoredhttps://en.wikipedia.org/wiki/Online_petition_on_Wikipedia_Muhammad_articlehttps://en.wikipedia.org/wiki/Online_petition_on_Wikipedia_Muhammad_articlehttps://en.wikipedia.org/wiki/English_Wikipediahttps://en.wikipedia.org/wiki/Muhammadhttps://en.wikipedia.org/wiki/Censorship_of_Wikipediahttps://en.wikipedia.org/wiki/Chinahttps://en.wikipedia.org/wiki/Pakistanhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/Wikipedia:Wikipedia_Loves_Librarieshttps://en.wikipedia.org/wiki/New_York_Public_Library_for_the_Performing_Arts

7.4 Explicit content 11

A 2011 study conducted by researchers at the Universityof Minnesota indicated that male and female editors fo-cus on different coverage topics. There was a greater con-centration of females in the People and Arts category,while males focus more on Geography and Science.[196]

7.3.1 Coverage of topics and selection bias

Research conducted by the Oxford Internet Institute hasshown that the geographic distribution of article topics ishighly uneven. Africa is most underrepresented.[197]

A selection bias may arise when more words per arti-cle are devoted to one public figure than a rival publicfigure. Editors may dispute suspected biases and discusscontroversial articles, sometimes at great length.

7.3.2 Systemic bias

When multiple editors contribute to one topic or set oftopics, there may arise a systemic bias, such as non-opposite definitions for apparent antonyms. In 2011,Wales noted that the unevenness of coverage is a reflec-tion of the demography of the editors, which predomi-nantly consists of young males with high education levelsin the developed world (cf previously).[133] The October22, 2013, essay by Tom Simonite in MITs TechnologyReview titled The Decline of Wikipedia discussed theeffect of systemic bias and policy creep on the downwardtrend in the number of editors.[71]

Systemic bias on Wikipedia may follow that of culturegenerally, for example favouring certain ethnicities ormajority religions.[198] It may more specifically followthe biases of Internet culture, inclining to being young,male, English-speaking, educated, technologically aware,and wealthy enough to spare time for editing. Biases ofits own may include over-emphasis on topics such as popculture, technology, and current events.[198]

Taha Yasseri of the University of Oxford, in 2013, stud-ied the statistical trends of systemic bias at Wikipedia in-troduced by editing conflicts and their resolution.[199][200]His research examined the counterproductive work be-havior of edit warring. Yasseri contended that simple re-verts or undo operations were not the most significantmeasure of counterproductive behavior at Wikipedia andrelied instead on the statistical measurement of detect-ing reverting/reverted pairs or mutually reverting editpairs. Such a mutually reverting edit pair is definedwhere one editor reverts the edit of another editor whothen, in sequence, returns to revert the first editor in themutually reverting edit pairs. The results were tabulatedfor several language versions of Wikipedia. The EnglishWikipedias three largest conflict rates belonged to the ar-ticles George W. Bush, Anarchism and Muhammad.[200]By comparison, for the German Wikipedia, the threelargest conflict rates at the time of the Oxford study werefor the articles covering (i) Croatia, (ii) Scientology and

(iii) 9/11 conspiracy theories.[200]

7.4 Explicit content

Main category: Wikipedia objectionable contentSee also: Internet Watch Foundation and Wikipedia andReporting of child pornography images on WikimediaCommons

Wikipedia has been criticized for allowing information ofgraphic content. Articles depicting arguably objection-able content (such as Feces, Cadaver, Human penis, andVulva) contain graphic pictures and detailed informationeasily available to anyone with access to the internet, in-cluding children.The site also includes sexual content such as images andvideos of masturbation and ejaculation, photographs ofnude children, illustrations of zoophilia, and photos fromhardcore pornographic films in its articles.The Wikipedia article about Virgin Killera 1976 albumfrom German heavy metal band Scorpionsfeatures apicture of the albums original cover, which depicts anaked prepubescent girl. The original release covercaused controversy and was replaced in some countries.In December 2008, access to the Wikipedia article VirginKiller was blocked for four days by most Internet serviceproviders in the United Kingdom after it was reportedby a member of the public as child pornography,[202] tothe Internet Watch Foundation (IWF), which issues a stoplist to Internet service providers. IWF, a non-profit, non-government-affiliated organization, later criticized the in-clusion of the picture as distasteful.[203]

In April 2010, Sanger wrote a letter to the Federal Bu-reau of Investigation, outlining his concerns that two cat-egories of images on Wikimedia Commons containedchild pornography, and were in violation of US federalobscenity law.[204] Sanger later clarified that the images,which were related to pedophilia and one about lolicon,were not of real children, but said that they constitutedobscene visual representations of the sexual abuse ofchildren, under the PROTECT Act of 2003.[205] Thatlaw bans photographic child pornography and cartoonimages and drawings of children that are obscene un-der American law.[205] Sanger also expressed concernsabout access to the images on Wikipedia in schools.[206]Wikimedia Foundation spokesman Jay Walsh strongly re-jected Sangers accusation,[207] saying that Wikipedia didnot have material we would deem to be illegal. If wedid, we would remove it.[207] Following the complaintby Sanger, Wales deleted sexual images without consult-ing the community. After some editors who volunteer tomaintain the site argued that the decision to delete hadbeen made hastily, Wales voluntarily gave up some ofthe powers he had held up to that time as part of his co-founder status. He wrote in a message to the WikimediaFoundation mailing-list that this action was in the inter-

https://en.wikipedia.org/wiki/University_of_Minnesotahttps://en.wikipedia.org/wiki/University_of_Minnesotahttps://en.wikipedia.org/wiki/Africahttps://en.wikipedia.org/wiki/Systemic_biashttps://en.wikipedia.org/wiki/Criticism_of_Wikipedia#Excessive_regulationhttps://en.wikipedia.org/wiki/Wikipedia#Decline_in_participation_since_2009https://en.wikipedia.org/wiki/Wikipedia#Decline_in_participation_since_2009https://en.wikipedia.org/wiki/Criticism_of_Wikipedia#Systemic_bias_in_coveragehttps://en.wikipedia.org/wiki/Internet_culturehttps://en.wikipedia.org/wiki/University_of_Oxfordhttps://en.wikipedia.org/wiki/Counterproductive_work_behaviorhttps://en.wikipedia.org/wiki/Counterproductive_work_behaviorhttps://en.wikipedia.org/wiki/George_W._Bushhttps://en.wikipedia.org/wiki/Anarchismhttps://en.wikipedia.org/wiki/Muhammadhttps://en.wikipedia.org/wiki/Croatiahttps://en.wikipedia.org/wiki/Scientologyhttps://en.wikipedia.org/wiki/9/11_conspiracy_theorieshttps://en.wikipedia.org/wiki/Category:Wikipedia_objectionable_contenthttps://en.wikipedia.org/wiki/Internet_Watch_Foundation_and_Wikipediahttps://en.wikipedia.org/wiki/Reporting_of_child_pornography_images_on_Wikimedia_Commonshttps://en.wikipedia.org/wiki/Reporting_of_child_pornography_images_on_Wikimedia_Commonshttps://en.wikipedia.org/wiki/Feceshttps://en.wikipedia.org/wiki/Cadaverhttps://en.wikipedia.org/wiki/Human_penishttps://en.wikipedia.org/wiki/Vulvahttps://en.wikipedia.org/wiki/Sexual_contenthttps://en.wikipedia.org/wiki/Masturbationhttps://en.wikipedia.org/wiki/Ejaculationhttps://en.wikipedia.org/wiki/Child_nudityhttps://en.wikipedia.org/wiki/Child_nudityhttps://en.wikipedia.org/wiki/Zoophiliahttps://en.wikipedia.org/wiki/Hardcore_pornographyhttps://en.wikipedia.org/wiki/Virgin_Killerhttps://en.wikipedia.org/wiki/Music_of_Germanyhttps://en.wikipedia.org/wiki/Heavy_metal_musichttps://en.wikipedia.org/wiki/Rock_bandhttps://en.wikipedia.org/wiki/Scorpions_(band)https://en.wikipedia.org/wiki/Prepubescenthttps://en.wikipedia.org/wiki/Virgin_Killerhttps://en.wikipedia.org/wiki/Virgin_Killerhttps://en.wikipedia.org/wiki/Internet_service_providerhttps://en.wikipedia.org/wiki/Internet_service_providerhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/Child_pornographyhttps://en.wikipedia.org/wiki/Internet_Watch_Foundationhttps://en.wikipedia.org/wiki/Wikimedia_Commonshttps://en.wikipedia.org/wiki/United_States_obscenity_lawhttps://en.wikipedia.org/wiki/United_States_obscenity_lawhttps://en.wikipedia.org/wiki/Pedophiliahttps://en.wikipedia.org/wiki/Loliconhttps://en.wikipedia.org/wiki/Child_pornography_laws_in_the_United_States#Section_1466Ahttps://en.wikipedia.org/wiki/Obscenity#United_States_obscenity_lawhttps://en.wikipedia.org/wiki/Obscenity#United_States_obscenity_lawhttps://en.wikipedia.org/wiki/Wikimedia_Foundation

12 8 OPERATION

est of encouraging this discussion to be about real philo-sophical/content issues, rather than be about me and howquickly I acted.[208] Critics, including Wikipediocracy,noticed that many of the pornographic images deletedfrom Wikipedia since 2010 have reappeared.[209]

7.5 Privacy

One privacy concern in the case of Wikipedia is the rightof a private citizen to remain a private citizen ratherthan a "public figure" in the eyes of the law.[210][notes 5] It isa battle between the right to be anonymous in cyberspaceand the right to be anonymous in real life ("meatspace").A particular problem occurs in the case of an individualwho is relatively unimportant and for whom there existsa Wikipedia page against her or his wishes.In January 2006, a German court ordered the GermanWikipedia shut down within Germany because it statedthe full name of Boris Floricic, aka Tron, a deceasedhacker. On February 9, 2006, the injunction againstWikimedia Deutschland was overturned, with the courtrejecting the notion that Trons right to privacy or that ofhis parents was being violated.[211]

Wikipedia has a Volunteer Response Team that usesthe OTRS system to handle queries without having to re-veal the identities of the involved parties. This is used,for example, in confirming the permission for using indi-vidual images and other media in the project.[212]

8 Operation

A group of Wikipedia editors may form a WikiProject tofocus their work on a specific topic area, using its associ-ated discussion page to coordinate changes across multi-ple articles.[213]

8.1 Wikimedia Foundation and the Wiki-media chapters

Main article: Wikimedia FoundationWikipedia is hosted and funded by the Wikimedia

Foundation, a non-profit organization which also oper-ates Wikipedia-related projects such as Wiktionary andWikibooks. The foundation relies on public contributionsand grants to fund its mission.[214] Wikimedia chapters,local associations of users and supporters of the Wikime-dia projects also participate in the promotion, develop-ment, and funding of the project. The foundations 2013IRS Form 990 shows revenue of $39.7 million and ex-penses of almost $29 million, with assets of $37.2 millionand liabilities of about $2.3 million.[215]

In May 2014, Wikimedia Foundation named LilaTretikov as its new executive director, taking over for SueGardner.[216] The Wall Street Journal reported on May

Wikimedia Foundation logo

1, 2014 that Tretikovs information technology back-ground from her years at University of California of-fers Wikipedia an opportunity to develop in more con-centrated directions guided by her often repeated posi-tion statement that, Information, like air, wants to befree.[217][218] The same Wall Street Journal article re-ported these directions of development according to aninterview with spokesman Jay Walsh of Wikimedia whosaid Tretikov would address that issue (paid advocacy)as a priority. 'We are really pushing toward more trans-parency... We are reinforcing that paid advocacy is notwelcome.' Initiatives to involve greater diversity of con-tributors, better mobile support of Wikipedia, new geo-location tools to find local content more easily, and moretools for users in the second and third world are also pri-orities, Walsh said.[217]

8.2 Software operations and support

See also: MediaWiki

The operation of Wikipedia depends on MediaWiki, acustom-made, free and open source wiki software plat-form written in PHP and built upon the MySQL databasesystem.[219] The software incorporates programming fea-tures such as a macro language, variables, a transclusionsystem for templates, and URL redirection. Medi-aWiki is licensed under the GNU General Public Li-cense and it is used by all Wikimedia projects, as well asmany other wiki projects. Originally, Wikipedia ran onUseModWiki written in Perl by Clifford Adams (PhaseI), which initially required CamelCase for article hyper-links; the present double bracket style was incorporatedlater. Starting in January 2002 (Phase II), Wikipediabegan running on a PHP wiki engine with a MySQLdatabase; this software was custom-made for Wikipedia

https://en.wikipedia.org/wiki/Wikipediocracyhttps://en.wikipedia.org/wiki/Privacyhttps://en.wikipedia.org/wiki/Public_figurehttps://en.wikipedia.org/wiki/Cyberspacehttps://en.wikipedia.org/wiki/Real_lifehttps://en.wikipedia.org/wiki/Meatspacehttps://en.wikipedia.org/wiki/German_Wikipediahttps://en.wikipedia.org/wiki/German_Wikipediahttps://en.wikipedia.org/wiki/Tron_(hacker)https://en.wikipedia.org/wiki/OTRShttps://en.wikipedia.org/wiki/Wikipedia:WikiProjecthttps://en.wikipedia.org/wiki/Wikimedia_Foundationhttps://en.wikipedia.org/wiki/Wikimedia_Foundationhttps://en.wikipedia.org/wiki/Wikimedia_Foundationhttps://en.wikipedia.org/wiki/Wiktionaryhttps://en.wikipedia.org/wiki/Wikibookshttps://en.wikipedia.org/wiki/Lila_Tretikovhttps://en.wikipedia.org/wiki/Lila_Tretikovhttps://en.wikipedia.org/wiki/Wikimedia_Foundationhttps://en.wikipedia.org/wiki/Conflict-of-interest_editing_on_Wikipediahttps://en.wikipedia.org/wiki/MediaWikihttps://en.wikipedia.org/wiki/MediaWikihttps://en.wikipedia.org/wiki/Free_softwarehttps://en.wikipedia.org/wiki/Open_source_softwarehttps://en.wikipedia.org/wiki/Wiki_softwarehttps://en.wikipedia.org/wiki/PHPhttps://en.wikipedia.org/wiki/MySQLhttps://en.wikipedia.org/wiki/Macro_(computer_science)https://en.wikipedia.org/wiki/Variable_(programming)https://en.wikipedia.org/wiki/Transclusionhttps://en.wikipedia.org/wiki/Web_templatehttps://en.wikipedia.org/wiki/URL_redirectionhttps://en.wikipedia.org/wiki/GNU_General_Public_Licensehttps://en.wikipedia.org/wiki/GNU_General_Public_Licensehttps://en.wikipedia.org/wiki/UseModWikihttps://en.wikipedia.org/wiki/Perlhttps://en.wikipedia.org/wiki/CamelCasehttps://en.wikipedia.org/wiki/PhpWiki

8.4 Wikiprojects, and assessments of articles importance and quality 13

by Magnus Manske. The Phase II software was repeat-edly modified to accommodate the exponentially increas-ing demand. In July 2002 (Phase III), Wikipedia shiftedto the third-generation software, MediaWiki, originallywritten by Lee Daniel Crocker.Several MediaWiki extensions are installed[220] to extendthe functionality of the MediaWiki software.In April 2005, a Lucene extension[221][222] was addedto MediaWikis built-in search and Wikipedia switchedfrom MySQL to Lucene for searching. The site currentlyuses Lucene Search 2.1,[223] which is written in Java andbased on Lucene library 2.3.[224]

In July 2013, after extensive beta testing, a WYSI-WYG (What You See Is What You Get) extension,VisualEditor, was opened to public use.[225][226][227][228]It was met with much rejection and criticism, and was de-scribed as slow and buggy.[229] The feature was turnedoff afterward.

8.3 Automated editing

Computer programs called bots have been used widelyto perform simple and repetitive tasks, such as correct-ing common misspellings and stylistic issues, or to startarticles such as geography entries in a standard formatfrom statistical data.[230][231][232] One controversial con-tributor massively creating articles with his bot was re-ported to create up to ten thousand articles on the SwedishWikipedia on certain days.[233] There are also some botsdesigned to automatically warn editors making commonediting errors (such as unmatched quotes or unmatchedparenthesis).[234] Edits misidentified by a bot as the workof a banned editor can be restored by other editors.An anti-vandal bot tries to detect and revert vandalismquickly and automatically.[231] Bots can also report ed-its from particular accounts or IP address ranges, as wasdone at the time of the MH17 jet downing incident in July2014.[235] Bots on Wikipedia must be approved prior toactivation.[236]

According to Andrew Lih, the current expansion ofWikipedia to millions of articles would be difficult to en-vision without the use of such bots.[237]

8.4 Wikiprojects, and assessments of arti-cles importance and quality

A "WikiProject" is a group of contributors who want towork together as a team to improve Wikipedia. Thesegroups often focus on a specific topic area (for example,womens history), a specific location or a specific kind oftask (for example, checking newly created pages). TheEnglish Wikipedia currently has over 2,000 WikiProjectsand activity varies. [238]

In 2007, in preparation for producing a print version, the

English Wikipedia introduced an assessment scale of thequality of articles.[239] Articles are rated by Wikiprojects.The range of quality classes begins with Stub (veryshort pages), followed by Start, C and B (in increas-ing order of quality). Community peer review is neededfor the article to enter one of the highest quality classes:either A, "good article" or the highest, "featured arti-cle". Of the about 4.4 million articles and lists assessedas of March 2015, a little more than 5000 (0.12%) arefeatured articles, and a little less than 2000 (0.04%) arefeatured lists. One featured article per day, as selected byeditors, appears on the main page of Wikipedia.[240][241]

The articles can also be rated as per importance asjudged by a Wikiproject. Currently, there are 5 impor-tance categories: low, mid, high, top, and "???"for unclassified/unsure level. For a particular article, dif-ferent Wikiprojects may assign different importance lev-els.The Wikipedia Version 1.0 Editorial Team has developeda table (shown below) that displays data of all rated arti-cles by quality and importance, on the English Wikipedia.If an article or list receives different ratings by two ormore Wikiprojects, then the highest rating is used inthe table, pie-charts, and bar-chart. The software reg-ularly auto-updates the data.Researcher Giacomo Poderi found that articles tend toreach featured status via the intensive work of a feweditors.[242] A 2010 study found unevenness in qualityamong featured articles and concluded that the com-munity process is ineffective in assessing the quality ofarticles.[243]

Quality-wise distribution of over 4.8 million articlesand lists on the English Wikipedia, as of 3 April2015[244]

Featured articles (0.11%)Featured lists (0.04%)A class (0.03%)Good articles (0.48%)B class (2.05%)C class (3.99%)Start class (25.73%)Stub class (54.08%)

https://en.wikipedia.org/wiki/Magnus_Manskehttps://en.wikipedia.org/wiki/Exponential_growthhttps://en.wikipedia.org/wiki/Exponential_growthhttps://en.wikipedia.org/wiki/Lee_Daniel_Crockerhttps://en.wikipedia.org/wiki/Lucenehttps://en.wikipedia.org/wiki/MySQLhttps://en.wikipedia.org/wiki/Java_(programming_language)https://en.wikipedia.org/wiki/VisualEditorhttps://en.wikipedia.org/wiki/Internet_bothttps://en.wikipedia.org/wiki/User:ClueBot_NGhttps://en.wikipedia.org/wiki/Andrew_Lihhttps://en.wikipedia.org/wiki/Wikipedia:Wikiprojecthttps://en.wikipedia.org/wiki/Social_grouphttps://en.wikipedia.org/wiki/Teamhttps://en.wikipedia.org/wiki/Women%2527s_historyhttps://en.wikipedia.org/wiki/English_Wikipediahttps://en.wikipedia.org/wiki/Wikipedia:Database_reports/WikiProjects_by_changeshttps://en.wikipedia.org/wiki/Wikipedia:Good_articleshttps://en.wikipedia.org/wiki/Wikipedia:Featured_articleshttps://en.wikipedia.org/wiki/Wikipedia:Featured_articleshttps://en.wikipedia.org/wiki/Main_pagehttps://en.wikipedia.org/wiki/Wikipedia:Version_1.0_Editorial_Team

14 8 OPERATION

Lists (3.50%)Unassessed (9.99%)

Importance-wise distribution of over 4.8 million arti-cles and lists on the English Wikipedia, as of 5 April2015[244]

Top (0.91%)High (3.21%)Medium (12.29%)Low (49.37%)??? (34.22%)500,0001,000,0001,500,0002,000,0002,500,0003,000,000TopHighMediumLow???

Featured articles

Featured lists

A-class articles

Good articles

B-class articles

C-class articles

Start-class articles

Stub articles

Lists

Unassessed articles and lists

[Note: The table above (prepared by the Wikipedia Ver-sion 1.0 Editorial Team) is automatically updated daily byUser:WP 1.0 bot, but the bar-chart and the two pie-chartsare not auto-updated. In them, new data has to be enteredby a Wikipedia editor (i.e. user).]

8.5 Hardware operations and support

See also: Wikimedia Foundation Hardware

Wikipedia receives between 25,000 and 60,000 pagerequests per second, depending on time of day.[245]Page requests are first passed to a front-end layer ofSquid caching servers.[246] Further statistics, based on apublicly available 3-month Wikipedia access trace, areavailable.[247] Requests that cannot be served from theSquid cache are sent to load-balancing servers running theLinux Virtual Server software, which in turn pass them toone of the Apache web servers for page rendering fromthe database. The web servers deliver pages as requested,performing page rendering for all the language editions ofWikipedia. To increase speed further, rendered pages arecached in a distributed memory cache until invalidated,allowing page rendering to be skipped entirely for mostcommon page accesses.Wikipedia currently runs on dedicated clusters of Linuxservers (mainly Ubuntu).[248][249] As of December 2009,there were 300 in Florida and 44 in Amsterdam.[250]By January 22, 2013, Wikipedia had migrated its pri-mary data center to an Equinix facility in Ashburn, Vir-ginia.[251][252]

Internet frontend Backend

Core services M

iscellaneous services

Apaches

36 Apache-Core/ext store

20 Apache-Core/ex-ES

149 Apache-Core

Load

-Bal

ance

rs

Databasess1: enwiki

Master 5 slaves

File servers

3 mass storage servers

Image scalers

6 scalers

Nagios

Subversion

Ganglia

IRCMail

OTRS tickets

IMAP Lists

Scratch hostsBatch jobs

LoggingLDAP/NIS

Network tools

DNS

NTP, SSH

APT repositories

HTML

Media files

Wikit

ext

Image files

Media

files

Image files

Database dumps

Search tasks

HTML + Media files

Toolserver DBs

Index updates

DB replication

SQL queries

Master DB Slave DB Apache Text squid Upload squid Load Balancer Search host Search indexer File server Image scaler Web service Mail/IRC service Network sevice

Search

Indexer

Toolserver

Web host Login

Tool hosts

s2: bg, cs, eo, ...

s7: es, hu, he, ...

s3: other wikis s4: commons s5: dewiki

s7: fr, ja, ru

Textstorage

page textDatabasedumps

dataset snapshot

(wikipedia, wiktionary, etc)

Amsterdam26 Text-Squids

29 Upload-Squids

Load-Balancer

Load- Balancer

Load- Balancer

4 'bits' Squids

Florida26 Text-Squids

Load- Balancer

Load- Balancer

4 'bits' Squids

26 Upload-Squids

Main cluster

Pdf

bugzillablogs

securetest.wiki

mobile donate

Other sites

applesearch

planet nagios project

transcode

HTML

Overview of system architecture, December 2010. See server lay-out diagrams on Meta-Wiki

8.6 Internal research and operational de-velopment

In accordance with growing amounts of incoming do-nations exceeding seven digits in 2013 as recentlyreported,[253] the Foundation has reached a threshold ofassets which qualify its consideration under the princi-

https://en.wikipedia.org/wiki/Wikipedia:Version_1.0_Editorial_Teamhttps://en.wikipedia.org/wiki/Wikipedia:Version_1.0_Editorial_Teamhttps://en.wikipedia.org/wiki/User:WP_1.0_bothttps://en.wikipedia.org/wiki/Wikimedia_Foundation#Hardwarehttps://en.wikipedia.org/wiki/Squid_(software)https://en.wikipedia.org/wiki/Linux_Virtual_Serverhttps://en.wikipedia.org/wiki/Cluster_(computing)https://en.wikipedia.org/wiki/Linuxhttps://en.wikipedia.org/wiki/Ubuntu_(operating_system)https://en.wikipedia.org/wiki/Amsterdamhttps://en.wikipedia.org/wiki/Equinixhttps://en.wikipedia.org/wiki/Ashburn,_Virginiahttps://en.wikipedia.org/wiki/Ashburn,_Virginiahttps://meta.wikimedia.org/wiki/Server%2520layout%2520diagramshttps://meta.wikimedia.org/wiki/Server%2520layout%2520diagrams

8.7 Internal news publications 15

ples of industrial organization economics to indicate theneed for the re-investment of donations into the internalresearch and development of the Foundation.[254] Two ofthe recent projects of such internal research and devel-opment have been the creation of a Visual Editor anda largely under-utilized Thank tab which were devel-oped for the purpose of ameliorating issues of editorattrition, which have met with limited success.[229][255]The estimates for reinvestment by industrial organiza-tions into internal research and development was stud-ied by Adam Jaffe who recorded that the range of 4%to 25% annually was to be recommended, with high endtechnology requiring the higher level of support for inter-nal reinvestment.[256] At the 2013 level of contributionsfor Wikimedia presently documented as 45 million dol-lars, the computed budget level recommended by Jaffeand Caballero for reinvestment into internal research anddevelopment is between 1.8 million and 11.3 million dol-lars annually.[256]

According to the Michael Porter five forces analysisframework for industry analysis, Wikipedia and its par-ent institution Wikimedia are known as first moversand radical innovators in the services provided andsupported by an open-source, on-line encyclopedia.[257]The five forces are centered around the issue of com-petitive rivalry within the encyclopedia industry whereWikipedia is seen as having redefined by its radical in-novation the parameters of effectiveness applied to con-ventional encyclopedia publication. This is the first forceof Porters five forces analysis.[258] The second force isthe threat of new entrants with competitive services andproducts possibly arising on the internet or the web. Asa first mover, Wikipedia has largely eluded the emer-gence of a fast second to challenge its radical innova-tion and its standing as the central provider of the ser-vices which it offers through the World Wide Web.[259]Porters third force is the threat of substitute prod-ucts and it is too early to identify Googles Knowl-edge Graphs as an effective competitor given the currentdependence of Knowledge Graphs upon Wikipediasfree access to its open-source services.[257] The fourthforce in the Porter five forces analysis is the bargainingpower of consumers who use the services provided byWikipedia, which has historically largely been nullifiedby the Wikipedia founding principle of an open invitationto expand and edit its content expressed in its moniker ofbeing the encyclopedia which anyone can edit.[258] Thefifth force in the Porter five forces analysis is defined asthe bargaining power of suppliers, presently seen as theopen domain of both the global internet as a whole andthe resources of public libraries world-wide, and there-fore it is not seen as a limiting factor in the immediatefuture of the further development of Wikipedia.[257]

8.7 Internal news publications

Community-produced news publications include theEnglish Wikipedia's The Signpost, founded in 2005 byMichael Snow, an attorney, Wikipedia administrator andformer chair of the Wikimedia Foundation board oftrustees.[260] It covers news and events from the site, aswell as major events from other Wikimedia projects, suchas Wikimedia Commons. Similar publications are theGerman-language Kurier, and the Portuguese-languageCorreio da Wikipdia. Other past and present commu-nity news publications on English Wikipedia include theWikiworld web comic, the Wikipedia Weekly podcast,and newsletters of specific WikiProjects like The Bu-gle from WikiProject Military History and the monthlynewsletter from The Guild of Copy Editors. Thereare also a number of publications from the Wikime-dia Foundation and multilingual publications such as theWikimedia Blog and This Month in Education.

9 Access to content

9.1 Content licensing

When the project was started in 2001, all text inWikipedia was covered by the GNU Free Documenta-tion License (GFDL), a copyleft license permitting theredistribution, creation of derivative works, and commer-cial use of content while authors retain copyright of theirwork.[261] The GFDL was created for software manualsthat come with free software programs licensed underthe GPL. This made it a poor choice for a general refer-ence work; for example, the GFDL requires the reprintsof materials from Wikipedia to come with a full copyof the GFDL text. In December 2002, the CreativeCommons license was released: it was specifically de-signed for creative works in general, not just for softwaremanuals. The license gained popularity among blog-gers and others distributing creative works on the Web.The Wikipedia project sought the switch to the CreativeCommons.[262] Because the two licenses, GFDL and Cre-ative Commons, were incompatible, in November 2008,following the request of the project, the Free SoftwareFoundation (FSF) released a new version of the GFDLdesigned specifically to allow Wikipedia to relicense itscontent to CC BY-SA by August 1, 2009. (A new versionof the GFDL automatically covers Wikipedia contents.)In April 2009, Wikipedia and its sister projects held acommunity-wide referendum which decided the switchin June 2009.[263][264][265][266]

The handling of media files (e.g. image files) varies acrosslanguage editions. Some language editions, such as theEnglish Wikipedia, include non-free image files underfair use doctrine, while the others have opted not to, inpart because of the lack of fair use doctrines in theirhome countries (e.g. in Japanese copyright law). Media

https://en.wikipedia.org/wiki/Industrial_organizationhttps://en.wikipedia.org/wiki/Porter_fi