Wikipedia information is free for anyone to use
Main article: Wikipedia:Copyright
Wikipedia contributions are voluntarily given under the GNU Free Documentation License (GFDL), which applies the legal principle known as copyleft, a way of using the copyright process to prevent information being controlled by any one person, to ensure it remains freely accessible forever.
All of the information in Wikipedia is free for anyone to copy, modify for their own purposes, and redistribute or use as they see fit, as long as the new version grants the same freedoms to others and acknowledges the authors of the Wikipedia article used (a credit or backlink to the original article is sufficient for this). For full information see the copyright page or the text of the GNU Free Documentation License.