Since Wikipedia is an educational and non-commercial site, members will sometimes contribute copyrighted material which is approved only for non-commercial or education-only use ("NC/EO" material). Unfortunately, such material is not permitted on the English Wikipedia. Textual content must be licenseable under the GFDL, which makes no provisions for whether or not the use of a work derives revenue or whether it is used for educational purposes or not, and Jimbo Wales made it clear in May 2005 that such restrictions on images were not permitted on Wikipedia in an e-mail to the WikiEN-l list:
All images which are for non-commercial only use and by permission only are not acceptable for Wikipedia and will be deleted. ... As of [May 19, 2005], all new images which are "non commercial only" and "with permission only" should be deleted on sight. Older images should go through a process of VfD to eliminate them in an orderly fashion, taking due account of "fair use".[1]
— Jimbo Wales
Because this policy is somewhat controversial and often misunderstood, this page is an attempt to make clear the rationale behind it, and to answer some of the most frequently asked questions about the policy. It is not intended to be a policy guideline, but rather to give some explanation behind the policies. None of the views expressed here are official, and none of them are uncontested or uncontestable.