Some materials are in the public domain, which means the intellectual property is not owned or controlled by any person or entity. Materials in the public domain can be used freely, although they may need to be properly cited. Determining copyright terms and what is in the public domain can be difficult; this site is an informational starting point.
Copyright Term and Public Domain This chart, developed by Peter B. Hirtle and maintained at the Cornell Copyright Information Center at Cornell University, lists copyright terms of various types of published and unpublished works, with dates those works fall into the public domain.
The Copyright Genie This tool can help users determine if a work is protected by copyright and by what terms.
Fair use allows users of copyrighted works the right to exercise without permission some of the rights normally reserved for copyright owners. This concept is used as a defense in a court of law. Determining what might be considered a fair use in court can be an uncertain process, but these tools can assist you in assessing your use of a copyrighted work.
Fair Use Evaluator Developed by Michael Brewer in cooperation with the ALA Office for Information Technology Policy, this interactive tool can help assist in evaluating whether or not use of a copyrighted work could be considered a fair use under U.S. Copyright Law.