Definition: According to the U.S. Copyright Office, 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 Copyright covers both published and unpublished works."
Under 17 USCS Section 102 the following is protected:
"In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work."
For example, consider the layout of buttons on a remote for a media player, such as “stop,” “play,” “reverse,” and “fast forward,” etc. Any manufacturer can use those common terms and could place buttons in a configuration like this that is intuitive to all users. That’s due to court rulings that prohibit companies from copyrighting “methods of operation”
The author(s) of the work, unless...
They were hired to create the work. In that case, their employers owns the copyright.
Or if the author(s) sold the copyright to their work to someone else, in which case the buyer owns the copyright.
Others deriving rights through or from the author(s) can include: publishers, record labels, descendants of the author, etc.
-Derived from the Standford Libraries' "Copyright and Fair Use"
The United States has had several copyright codes in its history, so depending on when a work was created, it may or may not be protected by copyright. Check out the American Library Association's Digital Copyright Slider to see if what you want to use is in the public domain or covered by copyright.
When the term of copyright expires (or an individual forfeits their copyrights using a CC0 license or something similar, see Creative Commons for more information), a work is said to enter into the public domain. Works created by employees of the United States federal government are not protected by copyright and are also included in the public domain.
Anyone may reproduce, redistribute, perform, or adapt works in the public domain. Permission for use is no longer required.
Due to the Copyright Term Extension Act of 1998 (also known as the Sonny Bono Act), no copyrighted works were eligible to enter the public domain until 2019. Now, creative works from 1925 or earlier are in the public domain and there will be a new batch of work entering the public domain each year (so on January 1, 2022, all works made in 1926 will go public, and so on each year).
© 2008 Tom Bell
The "first sale" doctrine says that a person who buys a legally produced copyrighted work may "sell or otherwise dispose" of the work as he or she sees fit, subject to some important exceptions (Section 109a). "First sale" gives you the right to loan a legally purchased book or CD to your friend. Historically libraries have heavily relied on the first sale doctrine to lend books and other items to their patrons.
The first sale clause was enacted during a time when most copyrighted works were produced in physical formats that made such works difficult to reproduce on a large scale. Many protected works including books are now produced digitally, however, copyright owners have lobbied Congress for new laws that some feel may undermine the "first sale" doctrine.
Additionally, many publishers (most notably music publishers) are now creating works to include technologies that interfere with the "first sale" doctrine. Software companies also attempt to circumvent the first sale doctrine by characterizing the consumer purchase as a license rather than a sale.
First sale issues are entangled with licensing and Digital Millennium Copyright Act issues. To learn more about The Digital Millennium Copyright Act please see the American Library Association's Introduction to the DMCA.