Wikipedia

• 1. Introduction

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  Wikipedia launched on the 15th of January 2001 as a single English-language web page with the domain name www.wikipedia.com. Nobody watching that moment could have predicted that what began as a side project for a struggling expert encyclopedia called Nupedia would become the largest reference work in human history. Today, Wikipedia draws more than 1.5 billion unique device visits every month and receives roughly 13 million edits in that same span, an average of about five edits per second. It is a place where the biography of a medieval emperor and the plot summary of a video game sit a few clicks apart, maintained almost entirely by volunteers who are never paid. How did a wiki launched by a web portal company become the world's most read encyclopedia? What happens when anyone can edit anything? And what does it mean that the planet's most consulted reference is written by a community that is predominantly male, predominantly Western, and almost entirely anonymous?

• 2. From Nupedia to Wikipedia

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  On the 9th of March 2000, a web portal company called Bomis launched Nupedia, a free online encyclopedia whose articles were written by credentialed experts and reviewed through a formal editorial process. Bomis CEO Jimmy Wales oversaw it, and the editor-in-chief was Larry Sanger. The project was painstaking. Nupedia operated under its own Nupedia Open Content License before switching to the GNU Free Documentation License at the urging of free software advocate Richard Stallman. Progress was slow, and the expert review process meant articles accumulated at a trickle. On the 10th of January 2001, Sanger proposed to the Nupedia mailing list a radical shortcut: create a wiki as a "feeder" project that could draft articles quickly before they entered the formal Nupedia pipeline. Wales is credited with defining the goal of a publicly editable encyclopedia; Sanger is credited with the strategy of using wiki software to get there. Wales has said his thinking about how to run Wikipedia was shaped by Friedrich Hayek's essay The Use of Knowledge in Society, which Wales described as "central" to his thinking. He was introduced to Hayek's ideas by libertarian economist Mark Thornton. The name Wikipedia itself was proposed by Sanger as a way to protect the Nupedia brand from any association with the looser project. Nupedia and Wikipedia ran side by side until 2003, when Nupedia's servers were shut down for good and its text was folded into Wikipedia.

• 3. Growth and Growing Pains

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  Language editions of Wikipedia began appearing in March 2001, and by the end of 2004, a total of 161 were in operation. Around 1,800 articles were being added to the English edition every day in 2006. By the 9th of September 2007, English Wikipedia passed 2 million articles, officially overtaking the Yongle Encyclopedia, a Chinese imperial reference work compiled during the Ming dynasty in 1408 that had held the record for almost 600 years. The edition reached 3 million articles in August 2009. But the pace was already slowing. By 2013 the daily article addition rate had dropped to roughly 800. A team at the Palo Alto Research Center traced the deceleration to "increased coordination and overhead costs, exclusion of newcomers, and resistance to new edits." A researcher at the Rey Juan Carlos University in Madrid found in November 2009 that the English Wikipedia had lost 49,000 editors in the first three months of that year alone, compared with only 4,900 departures during the same window in 2008. Wales initially disputed the figures, but by 2011 he acknowledged a decline, noting the count had slipped from "a little more than 36,000 writers" in June 2010 to 35,800 in June 2011. A 2013 article in MIT Technology Review reported that Wikipedia had lost a third of its volunteer editors since 2007. The English Wikipedia's active editor count peaked at roughly 50,000 in 2007 and had fallen to about 30,000 by the start of 2014, even as non-English Wikipedias held steady at approximately 42,000 active contributors.

• 4. Who Actually Writes It

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  Jimmy Wales once argued that the bulk of Wikipedia's contributions come from "a dedicated group of a few hundred volunteers." In 2009, Wales stated that "over 50% of all the edits are done by just 0.7% of the users... 524 people." Business Insider journalist Henry Blodget pushed back in the same year, finding in a random article sample that most surviving text was created by outsider contributors, even though insiders did most of the formatting and editing work. A 2008 Slate magazine article reported that one percent of Wikipedia users are responsible for about half of all edits. Aaron Swartz disputed even that framing, noting that in articles he sampled, large portions of the actual text were contributed by users with very low edit counts. The Wikimedia Foundation's own 2008 survey found that only 13 percent of Wikipedia editors were female. A comprehensive 2016 study by Julia B. Bear of Stony Brook University and Benjamin Collier of Carnegie Mellon University found that women reported less confidence in their expertise, greater discomfort with editing, and more negative responses to critical feedback compared to men. In May 2018, a Wikipedia editor rejected a submission about physicist Donna Strickland because she lacked sufficient coverage in independent sources. Five months later, Strickland won the Nobel Prize in Physics, becoming only the third woman to receive that award. Research by Mark Graham of the Oxford Internet Institute in 2009 found that Africa was the most underrepresented continent in terms of article coverage across Wikipedia's language editions.

• 5. Vandalism, Disputes, and the Rules That Followed

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  In May 2005, an anonymous editor inserted false information into the Wikipedia biography of John Seigenthaler, the founding editorial director of USA Today and founder of the Freedom Forum First Amendment Center at Vanderbilt University. The edit falsely presented Seigenthaler as a suspect in the assassination of John F. Kennedy, and it remained uncorrected for four months. Seigenthaler called Wales directly, asking whether Wikipedia had any way of identifying who had submitted the misinformation. Wales said it did not, though the perpetrator was eventually traced. Seigenthaler afterward described Wikipedia as "a flawed and irresponsible research tool." The incident prompted policy changes tightening standards for biographical articles about living people. Wikipedia's response to persistent disputes became increasingly structured over time. The number of policy pages grew from 44 in 2008 to 383 by 2013, with guideline pages rising from 248 to 449 in the same period. A 2013 study by Taha Yasseri of the University of Oxford found that the English Wikipedia's three highest conflict rates belonged to the articles on George W. Bush, anarchism, and Muhammad. The Arbitration Committee, which presides over the most serious disputes, relies on cautions and probations in 63 percent of cases and bans editors from specific articles in 43 percent. On the 18th of January 2012, the English Wikipedia went dark for 24 hours to protest two proposed U.S. laws, the Stop Online Piracy Act and the PROTECT IP Act. More than 162 million people viewed the blackout explanation page that day.

• 6. Accuracy, Bias, and the Question of Trust

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  A 2005 peer review published by the science journal Nature compared 42 scientific entries across Wikipedia and Encyclopaedia Britannica. The review found that the average Wikipedia science entry contained around four inaccuracies while Britannica contained about three. Britannica disputed the findings, and Nature published a rebuttal. Critics also challenged the study's sample size and method. Columnist Edwin Black wrote in 2010 that Wikipedia was a mixture of "truth, half-truth, and some falsehoods." In 2020, journalists Omer Benjakob and Stephen Harrison observed that media coverage of Wikipedia had shifted fundamentally over two decades, from treating it as an intellectual frivolity to calling it the "last bastion of shared reality" online. As of January 2023, English Wikipedia articles had been cited 92,300 times in scholarly journals, with the cloud computing article being the most cited single page. Wikipedia co-founder Larry Sanger, who left in 2002 to start competing sites, said by the mid-2020s that Wikipedia had become "propaganda" for a left-leaning establishment. In October 2025, Sanger published a reform proposal called "Nine Theses" criticizing ideological bias, lack of transparency in editor hierarchies, and what he called an ineffective consensus-based decision process. Wales responded to Wikipedia's 25th anniversary in his own way: his book The Seven Rules of Trust, published by Penguin Random House in October 2025, examined the principles of trust that he believed enabled Wikipedia's growth.

• 7. The Infrastructure Beneath the Pages

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  Wikipedia runs on MediaWiki, a free and open-source platform written in PHP and built on the MySQL database system, originally developed by Lee Daniel Crocker as the third phase of Wikipedia's software in July 2002. Before that, Wikipedia ran on UseModWiki, written in Perl by Clifford Adams, which required CamelCase for article links; the double-bracket link style came later. A PHP wiki engine with a MySQL database, custom-built for Wikipedia by Magnus Manske, served as the second phase starting in January 2002. Wikipedia's primary data center migrated to an Equinix facility in Ashburn, Virginia by the 22nd of January 2013. A second application data center opened in 2014 in Carrollton, Texas. In 2017, a caching cluster opened at an Equinix facility in Singapore, the first of its kind in Asia. A caching data center opened in Marseille, France in 2022 and another in Sao Paulo, Brazil in 2024, the first of its kind in South America. Since January 2024, the Wikimedia Foundation has reported a roughly 50 percent increase in bandwidth use, which it attributes largely to automated "scraper" bots collecting Wikipedia data to train large language models. In October 2025, the Foundation reported an estimated 8 percent decline in human page views compared to the same month in 2024, which it speculated reflects shifting search habits driven by generative AI and social media. In March 2026, an AI agent operating under the account TomWikiAssist edited Wikipedia directly; the account was blocked as an unapproved bot.