<p>Wikipedia's <a title="English Wikipedia" href="/wiki/English_Wikipedia">English edition</a> was launched on <a title="January 15" href="/wiki/January_15">January 15</a>, <a title="2001" href="/wiki/2001">2001</a>, as a complement to <a title="Nupedia" href="/wiki/Nupedia">Nupedia</a>, an expert-written and now defunct encyclopedia. The project is currently operated by the <a title="Wikimedia Foundation" href="/wiki/Wikimedia_Foundation">Wikimedia Foundation</a>, a <a title="Non-profit organization" href="/wiki/Non-profit_organization">non-profit organization</a> created by <a title="Jimmy Wales" href="/wiki/Jimmy_Wales">Jimmy Wales</a>, the co-founder of Wikipedia.<sup class="reference" id="_ref-foundercontroversy_1"><a title="" href="#_note-foundercontroversy">[2]</a></sup><sup class="reference" id="_ref-Dan_Mitchell_0"><a title="" href="#_note-Dan_Mitchell">[3]</a></sup><sup class="reference" id="_ref-David_Mehegan_0"><a title="" href="#_note-David_Mehegan">[4]</a></sup><sup class="reference" id="_ref-Brian_Bergstein_0"><a title="" href="#_note-Brian_Bergstein">[5]</a></sup><sup class="reference" id="_ref-The_Hive_0"><a title="" href="#_note-The_Hive">[6]</a></sup> Wikipedia has approximately 7.2 million articles in 251 languages,<sup class="reference" id="_ref-ListOfWikipedias_1"><a title="" href="#_note-ListOfWikipedias">[1]</a></sup> 1.7 million of which are in the English edition. It has steadily risen in popularity since its inception,<sup class="reference" id="_ref-AlexaStats_0"><a title="" href="#_note-AlexaStats">[7]</a></sup> and currently ranks among the top fifteen most-visited websites worldwide.<sup class="reference" id="_ref-0"><a title="" href="#_note-0">[8]</a></sup></p>

<p>Due to its open nature, critics have questioned Wikipedia's reliability and accuracy.<sup class="reference" id="_ref-Who_0"><a title="" href="#_note-Who">[9]</a></sup> The site has also been criticized for its susceptibility to <a title="Vandalism" href="/wiki/Vandalism">vandalism</a>,<sup class="reference" id="_ref-DeathByWikipedia_0"><a title="" href="#_note-DeathByWikipedia">[10]</a></sup> uneven quality, <a title="Systemic bias" href="/wiki/Systemic_bias">systemic bias</a> and inconsistencies,<sup class="reference" id="_ref-SangerElitism_0"><a title="" href="#_note-SangerElitism">[11]</a></sup> and for favoring <a title="Consensus" href="/wiki/Consensus">consensus</a> over <a title="Credential" href="/wiki/Credential">credentials</a> in its editorial process.<sup class="reference" id="_ref-AcademiaAndWikipedia_0"><a title="" href="#_note-AcademiaAndWikipedia">[12]</a></sup> Wikipedia's content policies<sup class="reference" id="_ref-PoliciesAndGuidelines_0"><a title="" href="#_note-PoliciesAndGuidelines">[13]</a></sup> and sub-projects set up by contributors seek to address these concerns.<sup class="reference" id="_ref-1"><a title="" href="#_note-1">[14]</a></sup> Two scholarly studies have concluded that vandalism is generally short-lived<sup class="reference" id="_ref-MIT_IBM_study_0"><a title="" href="#_note-MIT_IBM_study">[15]</a></sup> and that Wikipedia is generally as accurate as other encyclopedias.<sup class="reference" id="_ref-Rosenzweig_2006_0"><a title="" href="#_note-Rosenzweig_2006">[16]</a></sup></p>

<p>&nbsp;</p>

<h2><span class="mw-headline">Authorship and management</span></h2>