"Only one thing is impossible for God: To find any sense in any copyright law on the planet." - Mark Twain
A strict but accurate interpretation of copyright law and fair use. From the Copyright Clearing Center.
Consumer-friendly DIY legal guides to permission and fair use, plus copyrighting and licensing your own works.
Copyright Basics (PDF)
Look over this pamphlet introducing copyright, distributed by the U.S. Copyright Office.
Understand how and when to use copyrighted material for purposes of criticism, education, and more.
Fair use = copyrighted material copied for a limited, "transformative" purpose: comment, criticism, parody, new interpretation, etc. Fair use does NOT require you to pay a fee or get permission from the rights holder.
The American Library Association's handy Fair Use Evaluator tool will help you decide when use is fair.
Still have unanswered questions? Try using Columbia University's Fair Use Checklist (PDF).
The public domain contains creative works that are not protected under U.S. copyright law and free for anyone to use. Works usually enter the public domain because the copyright has expired or the rights holder didn't renew the copyright. Stanford University offers more information.
How do I know if a work is in the public domain?
Consult Peter Hirtle's useful chart illustrating Copyright and the Public Domain in the United States (2014).
Why is the public domain valuable?