Important note: The Wikimedia Foundation does not own copyright on Wikipedia article texts or illustrations. It is therefore pointless to email our contact addresses asking for permission to reproduce articles or images, even if rules at your company, school, or organization mandate that you ask web site operators before copying their content.
The only Wikipedia content you should contact the Wikimedia Foundation about are the trademarked Wikipedia/Wikimedia logos, which are not freely usable without permission.
Permission to reproduce and modify text on Wikipedia has already been granted to anyone anywhere by the authors of individual articles as long as such reproduction and modification complies with licensing terms (see below and Wikipedia:Mirrors and forks for specific terms). Images may or may not permit reuse and modification; the conditions for reproduction of each image should be individually checked. The only exceptions are those cases in which editors have violated Wikipedia policy by uploading copyrighted material without authorization, or with copyright licensing terms which are incompatible with those Wikipedia authors have applied to the rest of Wikipedia content. While such material is present on Wikipedia (before it is detected and removed), it will be a copyright violation to copy it. For permission to use it, one must contact the owner of the copyright of the text or illustration in question; often, but not always, this will be the original author.
The text of Wikipedia is copyrighted (automatically, under the Berne Convention) by Wikipedia editors and contributors and is formally licensed to the public under one or several liberal licenses. Most of Wikipedia's text and many of its images are co-licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License (CC BY-SA) and the GNU Free Documentation License (GFDL) (unversioned, with no invariant sections, front-cover texts, or back-cover texts). Some text has been imported only under CC BY-SA and CC BY-SA-compatible license and cannot be reused under GFDL; such text will be identified on the page footer, in the page history, or on the discussion page of the article that utilizes the text. Every image has a description page that indicates the license under which it is released or, if it is non-free, the rationale under which it is used.
The licenses Wikipedia uses grant free access to our content in the same sense that free software is licensed freely. Wikipedia content can be copied, modified, and redistributed if and only if the copied version is made available on the same terms to others and acknowledgment of the authors of the Wikipedia article used is included (a link back to the article is generally thought to satisfy the attribution requirement; see below for more details). Copied Wikipedia content will therefore remain free under an appropriate license and can continue to be used by anyone subject to certain restrictions, most of which aim to ensure that freedom. This principle is known as copyleft in contrast to typical copyright licenses.
To this end,
Permission is granted to copy, distribute and/or modify Wikipedia's text under the terms of the Creative Commons Attribution-ShareAlike 3.0 Unported License and, unless otherwise noted, the GNU Free Documentation License, unversioned, with no invariant sections, front-cover texts, or back-cover texts.
The English text of the CC BY-SA and GFDL licenses is the only legally binding restriction between authors and users of Wikipedia content. What follows is our interpretation of CC BY-SA and GFDL, as it pertains to the rights and obligations of users and contributors.