The Public Domain Exception to Copyright

When copyright protection expires, a work passes into the public domain. The work may be used by anyone for any reason in any way. For example, the novel Moby Dick is in the public domain. You may copy it, reproduce it, make a movie from the novel and so forth. Determining when the copyright protection has expired is difficult because the copyright laws have changed several times, and different laws and expiration dates apply to different works. However, works published prior to 1923 are in the public domain. (Beware of licensing agreements that limit your use of public domain works because you access the works through its services.)

Also, some works enter the public domain because they are dedicated to the public domain (such as government documents), or are not copyrightable by their nature (such as factual data). For more information, and links to free public domain materials, see: 

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