Copyright Guide

Fair use is a concept embedded in U.S. law that recognizes that certain uses of copyright-protected works do not require permission from the copyright holder. (See Title 17, section 107) 

The following four factors are used to determine if a use is fair:

1. The purpose of the use 
2. The nature of the copyrighted work 
3. The amount of the material used (the greater the amount copied, the less likely it is fair use)
4. The effect of use on the potential market for or value of the work