Wikipedia is a free, web-based and collaborative multilingual encyclopedia, born in the project supported by the non-profit Wikimedia Foundation. Its name is a portmanteau of the words wiki (a technology for creating collaborative websites, from the Hawaiian word wiki, meaning "quick") and encyclopedia. Wikipedia's 13 million articles (2.9 million in the English Wikipedia) have been written collaboratively by volunteers around the world, and almost all of its articles can be edited by anyone who can access the Wikipedia website. Proposed by Richard Stallman, it was launched in January 2001 by Jimmy Wales and Larry Sanger, it is currently the most popular general reference work on the Internet.
Critics of Wikipedia accuse it of systemic bias and inconsistencies, and allege that it favors consensus over credentials in its editorial process. Wikipedia's reliability and accuracy are also an issue. Other criticisms center on its susceptibility to vandalism and the addition of spurious or unverified information, though scholarly work suggests that vandalism is generally short-lived.
Jonathan Dee, of The New York Times, and Andrew Lih, in the 5th International Symposium on Online Journalism, have cited the importance of Wikipedia not only as an encyclopedic reference but also as a frequently-updated news resource because of how quickly articles about recent events appear.
When Time magazine recognized You as its Person of the Year for 2006, acknowledging the accelerating success of online collaboration and interaction by millions of users around the world, it cited Wikipedia as one of three examples of Web 2.0 services, along with YouTube and MySpace.