Rajiv Jhangiani of Kwantlen Polytechnic University gives a brief explanation of Open Educational Resources, their purpose and how they work (CC-BY).
The 5 "Rs," or permissions, as outlined by David Wiley, enable creators to set the terms for how their work can be used by others. Pay attention to the permissions the creator has given for the work you want to use, which often are noted in the Creative Commons license (see the "Creative Commons" box for more information). And if you're considering making your work open, consider what permissions you want others to have.
Source: Wiley, D. (2014, March 5). The access compromise and the 5th "R". Retrieved from https://opencontent.org/blog/archives/3221.)