Wikipedia, the world’s largest online encyclopedia and consistently one of the top ten most visited websites, was launched to little fanfare on January 15, 2001: it turns 20 today. Love it or hate it (and many librarians do both), it has had a tremendous impact on the internet and become nearly indispensable for a certain kind of easy information access.

While far from perfect, Wikipedia is a fascinating project, utterly unlike almost any other major website and one of the few success stories from the original open-access vision of the internet. Wikipedia now has more than 55 million articles in over 300 languages; as Louis Menand wrote recently in the New Yorker (“What Do You Know? Wikipedia, ‘Jeopardy’ and the Fate of the Fact”), the last print edition of the Encyclopaedia Britannica in 2012 had only around 65,000. The breadth and currency of Wikipedia eternally surprises: for example, Menand notes that each of New York City’s 472 subway stations has its own Wikipedia page. It is a non-profit endeavor written and edited by a huge community of unpaid non-expert volunteers "Wikipedians", but structured and run on principles that have, so far, tended to make it more or less self-correcting and reliable. It is also beset by controversies and constantly battling misinformation and vandalism—one helpful place to peruse its many failings is on the Wikipedia page, Criticisms of Wikipedia. It is shallow, dully written, and often justifiably accused of gender, racial and political bias. Its contributors and editors are overwhelmingly male, despite frequent outreach campaigns to female contributors. Wikipedia is not a source of original research, in-depth understanding, or well-turned prose; it is an information aggregator, and a flawed one, though also extremely useful, freely accessible to all and unburdened by commercial ads. A Washington Post header sums it up nicely: “Wikipedia Was Born in 2001, And the World Got a Bit Truthier.”

Much of the vision of the early internet pioneers who came out of the hippie movement was for something like Wikipedia (although looking back from 2021, things obviously took a turn). Among many manifestos for free open-source software circulating at the time, programmer Ward Campbell crystallized the egalitarian idea of the ‘wiki’ in the early 1990s: a hypertext publication written and edited collaboratively online by its own audience. He called it “the simplest online database that could actually work”, but did not copyright it, thinking it did not sound like an idea anyone would pay money for. He created the first wiki software, The WikiWikiWeb, in 1995. ‘Wiki’ is a Hawaiian word meaning ‘quick’, which Campbell first heard at the Honolulu Airport when he was directed to take the Wiki Wiki Shuttle bus as the quickest way between terminals.

In the late 1990s, internet entrepreneur Jimmy Wales and his chief editor Larry Sanger were working on Nupedia, intended to be a free online encyclopedia written and peer-reviewed by experts. Wales embraced the idea that Nupedia could encourage public contributions and editing, and Sanger saw that open-access wiki software could be used to accomplish that. To this end, they launched a companion site they called Wikipedia on January 15, 2001, with its first edit, the words “Hello World”, and announced it on the Nupedia mailing list. One of the first Wikipedia articles was on the letter Q. By mid-February there were a thousand articles; by 2006 there were a million. Sanger left disillusioned in 2002, in part over the role of experts in content creation; he later started Citizendium.org, hoping to provide more reliable content and stronger oversight. (The many alternatives to Wikipedia are a kind of tribute to its impact: Conservapedia, to correct pesky liberal bias; RationalWiki, to combat Conservapedia; PaganPedia, for topics of interest to pagans; Wookieepedia, for the Star Wars fan community, and so on.)

What problems arise, and how does Wikipedia overcome them? Its gigantic volunteer community of unpaid writers and editors, which the general public is openly welcomed to join, are the key to both. One of its first major controversies, the list is long, was a 2005 incident in which an unregistered editor posted a nefarious hoax on the page of journalist John Siegenthaler linking him to the Kennedy assassinations, which went undetected for months until noticed and corrected. Siegenthaler called for more government oversight of the internet, the desirability of which depends on who is running the government at the moment; Wales improved Wikipedia’s registration and oversight policies. Many later studies of Wikipedia concluded that hoaxes like this were the exception rather than the rule. The self-policing Wikipedian community assiduously roots out this sort of trouble, kicks out trolls, and has developed elaborate safeguards; articles prone to mendacity, such as ones covering controversial public figures, are locked down more strictly to editing and overseen more carefully, etc. An unfortunate side effect of this is that the writer/editor community can seem hierarchical and sometimes hostile to newcomers. Dariusz Jemielniak joined the Wikipedia community to investigate internal issues and concluded in Common Knowledge?: An Ethnography of Wikipedia (2014) that public perceptions of inmates running the asylum are greatly overstated. The nonprofit nature of Wikipedia and the low profile of its writers and editors also tends to produce a more sedate product, freer from the distortions of sites that depend on ads: sensationalism, grandstanding, hyperbole, misleading clickbait, etc.

One of the best things about Wikipedia is its transparency. Hardly anyone does this, but at the top of any article, you can click on the edit history, and see who changed what when. The availability of this public record is how Wired magazine discovered in 2005 that Jimmy Wales had been editing his own Wikipedia page, to minimize Larry Sanger’s role in the founding narrative; Wales admitted it was in bad taste and later relented. Menand also observes that Wikipedia cannot really take credit for its own accuracy. Every fact presented in a Wikipedia page is required to be cited by a reliable publication in the endnotes; Wikipedia users can easily identify suspicious articles by the many ‘citation needed’ notifications. Though Wikipedia is free, each of those cited publications is paid for by someone else: a magazine, a newspaper, even an old-fashioned encyclopedia. Wikipedia aggregates these outside sources, most of which were originally researched and written in-depth by experts trying to make a living. Appreciate Wikipedia for what it is: a remarkable community encyclopedia, a fast, self-critical, constantly updated compendium of information that is freely and easily accessible to all—but in no way a replacement for serious research or inquiry.