[Linda Buquet]

This is the 1st thing I found with a quick search.

"The "fair use" of a copyrighted work, including use for purposes such as criticism, comment, news reporting, teaching, scholarship, or research, is not an infringement of copyright. Copyright owners are, by law, deemed to consent to fair use of their works by others.

The Copyright Act does not define fair use. Instead, whether a use is fair use is determined by balancing these factors:

* The purpose and character of the use.
* The nature of the copyrighted work.
* The amount and substantiality of the portion used in relation to the copyrighted work as a whole.
* The effect of the use on the potential market for, or value of, the copyrighted work."

I got that from FindLaw and it's a very in-depth article. Read the rest here.