Open Educational Resources are teaching, learning, and research resources that reside in the public domain or have been released under an intellectual property license that permits their free use and repurposing by others.
OERs allow people to:
Retain - the right to make, own, and control copies of the content
Reuse - the right to use the content in a wide range of ways
Revise - the right to adapt, adjust, modify, or alter the content itself
Remix - the right to combine the original or revised content with other material to create something new
Redistribute - the right to share copies of the original content, your revisions, or your remixes with others