Wikipedia is a free-access, free content Internet encyclopedia, supported and hosted by the non-profit Wikimedia Foundation. Those who can access the site and follow its rules can edit most of its articles. Wikipedia is ranked among the ten most popular websites and constitutes the Internet's largest and most popular general reference work.
Wikipedia was created by Jimmy Wales and Larry Sanger. They launched the site on January 15, 2001. More: en.wikipedia.org.