As a general rule, most works enter the public domain because of old age. This includes any work published in the United States before 1923 or works published before 1964 for which copyrights were not renewed. (Renewal was a requirement for works published before 1978.) A smaller group of works fell into the public domain because they were published without a copyright notice, which was necessary for works published in the United States before March 1, 1989. Some works are in the public domain because the owner has indicated a desire to give them to the public without copyright protection.

Examples of characters and works in the public domain:
-The King in Yellow
-King Arthur and the Knights of the Round Table
-Shakespearean works
-Frankenstein and his monsters
-Dracula
-The Greek Comedies and Tragedies
-Inferno, Purgatorio and Paradiso
-The Tale of Genji
-The Bible, Koran and most other holy books
-Huckleberry Fin
-Tom Sawyer
-Night of the Living Dead


Examples of characters and works not in the public domain:
-Harry Potter
-Sookie Stackhouse
-A Game of Thrones
-The Phantom of the Opera
-The View Askew Universe
-The Twilight Saga
-Drizzt Do'Urden