Please note: The information on this guide has been prepared by librarians for general information purposes only and should not be construed as, nor substituted for, legal advice. It is strongly advised that you contact an attorney for legal advice.
Copyright is law established in the U.S. Constitution that protects the intellectual property of an author, giving them the exclusive rights to their materials for a set period of time. Works protected through copyright can be "literary, dramatic, musical, or artistic works, such as poetry, novels, movies, songs, computer software, and architecture" ("Copyright").
Copyright protects the author from having their work "reproduced, distributed, performed, publicly displayed, or made into a derivative work" without their expressed permission, with the exclusive right to charge money for the use of their work ("Definitions").
Copyright protection has expanded over time. Under current copyright laws, works are protected for the life of the author plus 70 years following the author's death. Anonymous works (no author) are protected for 95 years from publication or 120 years from creation (whichever is shorter).
A work no longer protected by copyright is considered in the public domain, which means that it can be reproduced, distributed, performed, publicly displayed, or made into a derivative work.
No permission is needed to make use of works in the public domain.
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The standard symbol for copyright is a lowercase "c" within a circle. It does not need to be displayed in order for something to be copyright protected.