Wikipedia

Wikipedia is a collaboratively edited, multilingual, free Internet encyclopedia supported by the non-profit Wikimedia Foundation. Wikipedia's 30 million articles in 286 languages, including over 4.2 million in the English Wikipedia, are written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone having access to the site and not being blocked. It is the largest and most popular general reference work on the Internet, ranking seventh globally among all websites on Alexa as of June 2013, and having an estimated 365 million readers worldwide.