Copyright is a form of intellectual property protection that grants creators exclusive rights to their original works of authorship. Under U.S. law, copyright protection arises automatically when an original work is fixed in a tangible medium of expression. The owner receives a bundle of exclusive rights, including the rights to reproduce, distribute, display, perform, and create derivative works based on the original.
Copyright protects original works of authorship that are fixed in a tangible medium. Protected categories include:
Literary works such as books, articles, poems, and computer code. Musical works including compositions and sound recordings. Dramatic works like plays and screenplays. Pictorial, graphic, and sculptural works encompassing paintings, photographs, sculptures, and architectural designs. Motion pictures and audiovisual works covering films, television shows, and video content. Sound recordings as distinct from the underlying musical compositions.
The work must demonstrate a minimal level of creativity and originality, though the threshold is quite low. Copyright does not protect ideas themselves, only the particular expression of ideas. Facts, procedures, processes, systems, methods of operation, concepts, principles, and discoveries are not copyrightable, regardless of how they are described or explained.
Several categories of material remain outside copyright protection. Ideas, facts, and information cannot be copyrighted, only their specific expression. Titles, names, short phrases, and slogans typically lack sufficient creativity, though they may qualify for trademark protection. Works by the U.S. government are generally in the public domain, though this doesn't extend to works by state and local governments or government contractors.
Purely functional elements without creative expression are not protected. Works that lack originality or consist entirely of commonly known information receive no copyright protection.
Copyright duration has evolved significantly throughout U.S. history. Under current law, works created on or after January 1, 1978, are protected for the life of the author plus 70 years. For works made for hire, anonymous works, or pseudonymous works, protection lasts 95 years from first publication or 120 years from creation, whichever is shorter.
Works published before 1978 follow different rules. Works published before 1928 are in the public domain. Works published between 1928 and 1963 received an initial 28-year term, renewable for another 28 years (now extended to 67 years for the renewal term). Works published between 1964 and 1977 received automatic renewal, providing 95 years of total protection from publication.
The public domain consists of works not protected by copyright, either because protection has expired, was forfeited, or never existed. Public domain works can be used by anyone for any purpose, including commercial use, without permission or payment.
Works enter the public domain through several mechanisms. Expiration of copyright terms represents the most common path. In the United States, works published before 1928 are definitively in the public domain. Each January 1st, additional works from 95 years prior enter the public domain.
Government works created by federal employees in their official capacity are immediately public domain. Dedication to the public domain occurs when creators explicitly relinquish their rights. Forfeiture historically happened when creators failed to comply with formalities like copyright notice or renewal, though this is less common under current law.
Fair use provides important limitations on copyright, allowing limited use of protected works without permission for purposes such as criticism, comment, news reporting, teaching, scholarship, or research. Courts evaluate fair use claims using four factors: the purpose and character of use (including whether it's commercial or educational), the nature of the copyrighted work, the amount and substantiality of the portion used, and the effect on the market for the original work.
Fair use analysis is highly fact-specific and contextual. Transformative uses that add new purpose or meaning are more likely to qualify. Educational and non-commercial uses receive more favorable treatment, though commercial use doesn't automatically preclude fair use. Using small portions of a work favors fair use, but even minimal use can be problematic if it represents the "heart" of the work.