Fair Use is a legal doctrine in U.S. copyright law that allows limited use of copyrighted material without requiring permission from the rights holders, typically for purposes such as criticism, comment, news reporting, teaching, scholarship, or research. The determination of fair use is case-specific, based on four factors: the purpose and character of the use, the nature of the copyrighted work, the amount and substantiality of the portion used, and the effect of the use on the market for the original work.