Fair Use is one means by which copyrighted works can be used without obtaining permission from the copyright holder. Fair Use is limited, but flexible, and is commonly used in educational settings.
Conducting a Fair Use analysis requires weighing four factors for each individual use, and seeing if, on balance the use is a fair one. Sometimes, the use is clear-cut. Other times, it's a judgment call, and two people analyzing the same situation can come up with different outcomes. Such is the nature of Fair Use.
The four factors are:
Each use is evaluated individually by doing a Fair Use test. Legally, there is no maximum number of pages nor percentage of the whole that determines Fair Use.
Use the Fair Use Checklist to evaluate each particular use.
The Association of Research Libraries has released a code of best practices that will be helpful in determining how we apply fair use in academic communities. -- 1/26/2012
The remedies provided by the law to a copyright owner mean that an individual found making illegal copies, or otherwise infringing, could face some very unpleasant consequences: