More than two decades ago (i.e. on 15 January 2001), 2 American entrepreneurs - Jimmy Wales and Larry Sanger - launched an online encyclopedia called 'Wikipedia'. Despite much criticism early on about inaccuracies among scholars and educators, it has gone on to be hugely successful. Overseen by the nonprofit Wikimedia Foundation, Wikipedia is now one of the most-visited sites on the Internet. It is now available in more than 300 languages and is maintained by a community of volunteer editors. According to Wikimedia foundation, people around the world look to Wikipedia around 21 billion times every month for information on everything from politics, to music, sports, and beyond. Over 20 years, it has become the largest collection of open knowledge in human history. Wikipedia is actually a manifestation of the power of human collaboration, creativity, and curiosity. But, how has Wikipedia, built on a model of radical collaboration, remained true to its original mission of "free access to the sum of all human knowledge" when other tech phenomena have devolved into advertising platforms?

The MIT publication "Wikipedia @ 20: Stories of an Incomplete Revolution", edited by academic and author Dr. Joseph M. Reagle, Jr. and social Scientist Dr. Jackie Koerner, is a collection of essays about Wikipedia. In this book, 34 academics, researchers, scholars, activists, journalists and volunteers reflect on Wikipedia's first twenty years, revealing connections across disciplines and borders, languages and data, the professional and personal. They consider Wikipedia's history, the richness of the connections that underpin it, and its founding vision. Their essays and articles look at, among other things, the shift from bewilderment to respect in press coverage of Wikipedia; Wikipedia as "the most important laboratory for social scientific and computing research in history"; and the acknowledgment that "free access" includes not just access to the material but freedom to contribute-that the summation of all human knowledge is biased by who documents it.

The book contains 21 chapters grouped into three main sections: I) Hindsight, II) Connection and III) Vision, followed by a fourth one - Capstone. The first section includes five chapters which are retrospective; they are mini-histories on how.

Wikipedia has been produced and discussed relative to internal and external tensions- such as the encyclopedia's conflict of interest policy. And the insight from these hindsights is that events flow in ways contrary and unexpected. The authors think that the peer-based production that the encyclopedia heralded had much utopian potential, but time has revealed unforeseen limitations; and among the many things Wikipedia is not, it is not a newspaper, but its content and readership is driven by the news. The second section containing eight chapters demonstrates the richness of connections. Wikipedia spans national, cultural, and linguistic divides as well as those between people, data, and machines. Wikipedia has even become "the most important laboratory for social scientific and computing research in history," as one pair of contributors show.

The third section of the book contains eight chapters which shed light on Wikipedia's founding vision, best expressed in the famous provocation to "imagine a world in which every single person on the planet is given free access to the sum of all human knowledge." The book concludes with a capstone from Katherine Maher, the then executive director of the Wikimedia Foundation. She reflects on the past, present, and future of Wikipedia, informed by Wikimedia 2030, the vision and strategy project by the global Wikimedia movement and free knowledge partners.

The writer is an independent researcher. E-mail: smrayhanulislam@hotmail.com