Open educational resources are and always will be free, but not all free resources are OER. Free resources may be temporarily free or may be restricted from use at some time in the future (including by the addition of fees to access those resources). Moreover, free-but-not-open resources may not be modified, adapted or redistributed without obtaining special permission from the copyright holder.
The above text is licensed under a Creative Commons Attribution (CCBY) 4.0 International License. Adapted by Nicole Allen of SPARC (email@example.com) from “#GoOpen: OER for K-12 Educators” (www.tinyurl.com/GoOpen) by Doug Levin, also available under a CCBY license.