A public domain work is a creative work that is not protected by copyright and which may be freely used by everyone. The reasons that the work is not protected include:

1. the term of copyright for the work has expired;
2. the author failed to satisfy statutory formalities to perfect the copyright; or
3. the work is a work of the U.S. Government.

In order to determine if the work you would like to use is protected by copyright or in the public domain, please view Cornell Copyright Information Center's Public Domain Chart (PDF).