Fair use is an exception to copyright law that permits the reproduction of a portion of a copyrighted work for the sake of research, teaching, and commentary without need of asking the copyright owner's permission. This is a vitally important exception for education as it enables students, scholars, and critics to use and reference copyrighted works in their own scholarship, teaching, and critiques.
Section 107 of the U.S. Copyright Act establishes four factors to be weighed in determining fair use:
Using copyrighted material for teaching is always fair use, right?
Not necessarily. The "purpose of the use" factor heavily favors educational, nonprofit, and public good use. But, a fair use analysis must weigh all four factors to arrive at a sound determination.
If you're not making money from it, it must be fair use, right?
Wrong. Not making money off using copyrighted material does not guarantee a fair use determination. You can use copyrighted material without any financial gain and still affect the work's market negatively.
If you use more than 50% of a work, you cannot claim fair use, right?
Not necessarily. While the "amount" factor specifies using non-essential portions of the work in modest amounts, it also indicates that the use must be appropriate to the purpose. In some cases that can even mean using all of the copyrighted work.
If you provide a citation and give credit where credit is due, then your use of copyrighted material is fair use, right?
This is not the case. While attribution is always appropriate in scholarly and educational activity, copyright law does not require citation. Again, weighing all four factors is what will determine whether it's fair use.
If you can use copyrighted materials in the classroom, then you can also use them online, right?
Wrong. Materials for online teaching require their own fair use analysis. This analysis would have to take into account the specifics on the digital environment.
The Technology, Education, and Copyright Harmonization Act or TEACH Act (2002) expanded educators' right to use copyrighted material in digital environments under limited conditions without securing permissions. The limited conditions map overall to the fair use framework, expanding it specifically to online environments. Some differences include: the TEACH Act applies specifically to nonprofit, accredited educational educational institutions and students must be informed that the material in question is protected by copyright law.
For a more in-depth review of the TEACH Act, see research guides by the University of Minnesota Libraries and Cornell University Library.