Copyright protects a vast array of materials, such as books, articles photographs, paintings, sculptures, software, websites, architecture, pantomimes, ballets, music, sound recordings, and even doodles, scribbles and graffiti. Copyright does not apply to facts, slogans, titles, and simple phrases. Also exempt from protection are works of the U.S. Government (be careful: the exemption does not apply to works created by state, local, or foreign governments).
Works are protected automatically as soon as they are created. An original work that is "fixed" by some media receives a degree of copyright protection immediately. It is no longer a requirement that a copyright notice be placed on the work or that the work be registered with the U.S. Copyright Office to receive protection. However, including a notice on your work and registering your work with the U.S. Copyright Office does provide some legal and practical benefits to the originator of the work.
When a work becomes available for use without permission from a copyright owner, it is said to be "in the public domain." Most works enter the public domain because their copyrights have expired.
To determine whether a work is in the public domain and available for use without the author's permission, you first have to find out when it was published. Then apply the following rules to see if the copyright has expired:
Notwithstanding the provisions of sections 106 and 106A , the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright.
In determining whether the use made of a work in any particular case is fair use, please refer to the Fundamentals of Copyright and Fair Use Guidelines developed by the Office of General Counsel, The California State University, dated July 2007 and posted on their web site.
Interactive Fair Use Factors Checklist, F-3798.