Copyright is a form of protection grounded in the U.S. Constitution and granted by law for original works of authorship fixed in a tangible medium of expression. Copyright covers both published and unpublished works.
Copyright, a form of intellectual property law, protects original works of authorship including literary, dramatic, musical, and artistic works, such as poetry, novels, movies, songs, computer software, and architecture. Copyright does not protect facts, ideas, systems, or methods of operation, although it may protect the way these things are expressed.
Section 106 of the 1976 Copyright Act generally gives the owner of copyright the exclusive right to do and to authorize others to do the following:
“Copyright Basics,” United States Copyright Office. Accessed October 28, 2009. <http://www.copyright.gov/circs/circ1.pdf [PDF]>
Let's say someone performs a dance for you--in person. That dance is not protected because it does not have a tangible form. However, if you record the dance, the recording of the dance has tangible form and is protected by copyright law at the moment of the recording.