- Copyrights protect a wide range of creative works including literary, musical and pictorial works as well as films, sound recordings, sculptures, architectural designs and computer programs. The only absolute requirements for protection are that the work must be original, and that it must be expressed in a tangible medium. Copyrights do not protect ideas, only the expression of ideas. Furthermore, the medium of expression must be permanent--a story that is told orally is not copyrightable, for example, until it has been written down or at least recorded in audio.
- In the United States, a copyright attaches the moment an original work is created and reduced to a tangible medium, regardless of whether the copyright is registered or even claimed by the author. Nevertheless, registration with the U.S. Copyright Office is available and is recommended in order to produce sufficient evidence of copyright to ensure effective enforcement. The author of a copyrightable work can contract with another party (such as a corporation) to create a "work for hire," which results in the copyright being owned by the corporation, not the actual author.
- The Fair Use Doctrine holds that people may freely use small portions of a copyrighted work without violating the copyright. An example would be using one line of a song or a paragraph from a book. The problem is that there is no clear legal rule detailing exactly what constitutes "fair use." It depends on the length of the original work, the importance of the portion to the work as a whole, and many other factors as determined on a case-by-case basis.
- The First Sale Doctrine holds that a copyright only protects the first sale of a particular copy of a work--which is why second-hand book stores, for example, do not have to pay royalties to the authors of the books they sell.
- The United States, like most of the nations of the world, is a member of the Berne Convention for the Protection of Literary and Artistic Works. This means that the creator of a copyrightable work in the United States automatically obtains copyright protection under the copyright laws of all Berne Convention countries, without the need to register the copyright in those countries.
- Works created or published since 2002 are entitled to automatic copyright protection for 70 years beyond the death of the author. Different rules apply to works owned by a corporation, such as works for hire, or for works first created or published before 2002 (see Resources section). After the copyright expires, the work is said to enter the "public domain," as with the works of Shakespeare, for example, and may be freely used and published as long as proper attribution is given to the author.
