Copyright in the United States

The Copyright Law of the United States tries to encourage the creation of art and culture by rewarding authors and artists with a set of exclusive rights. Copyright law grants authors and artists the exclusive right to make and sell copies of their works, the right to create derivative works, and the right to perform or display their works publicly. These exclusive rights are subject to a time limit, and generally expire 70 years after the author's death. In the United States, any music composed before January 1, 1923, is generally considered public domain.

United States copyright law is governed by the Copyright Act of 1976. The United States Constitution explicitly grants Congress the power to create copyright law under Article 1, Section 8, Clause 8, known as the Copyright Clause. Under the Copyright Clause, Congress has the power:

To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries.

The United States Copyright Office handles copyright registration, recording of copyright transfers, and other administrative aspects of copyright law.

US copyright law traces its lineage back to the British Statute of Anne, which influenced the first US federal copyright law, the Copyright Act of 1790. The Copyright Act has been updated several times, including, notably, the Copyright Act of 1976 and the Sonny Bono Copyright Term Extension Act of 1998 (also called the "Mickey Mouse Protection Act", because it prevented the copyright from expiring on the first commercial success of the cartoon character Mickey Mouse).

The goal of copyright law, as set forth in the US Constitution, is "to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." This includes incentivizing the creation of art, literature, architecture, music, and other works of authorship. As with many legal doctrines, the effectiveness of copyright law in achieving its stated purpose is a matter of debate.

...
Wikipedia