Creative Commons Copyright is at the heart of the OER movement. CCC allows creators to specify more flexible forms of copyright that allows "others to copy, distribute, and make some uses of their work."
Look for copyright information (often at the bottom of webpages). Creative Commons copyrighted material sometimes display clickable icons that indicate the specifics of licensing.
See the Creative Commons website for more info and to acquire license icons. http://us.creativecommons.org/
Meredith Keen-Wilson has put together a helpful tutorial about Creative Commons Copyright.
In general, US Copyright Law prohibits unauthorized reproduction and distribution of copyrighted works. However, the "Fair Use Doctrine" (Section 107) allows a limited amount of copying for purposes such as teaching and scholarship. In determining whether the use made of a work in a particular case is a Fair Use, the factors to be considered include:
Fair Use raises almost as many questions as it answers, and is a real source of concern for teachers. The most important point to remember is that Fair Use is both a right and a privilege, and does provide a substantial degree of freedom and protection for teachers. However, that freedom is often challenged, and in reality most educational institutions do not have the resources, skill, or willpower to engage in long and expensive legal battles over this issue.
The Fair Use Checklist can be helpful in determining whether or not usage falls under Fair Use.
This information is from LCC's Fair Use and Copyright guide.