Open Educational Resources are teaching, learning and research materials in any medium – digital or otherwise – that reside in the public domain or have been released under an open license that permits no-cost access, use, adaptation and redistribution by others with no or limited restrictions.
From UNESCO. This Guide comprises three sections. The first is a summary of the key issues. The second section is a more comprehensive analysis of these issues. The third section is a set of appendices, containing more detailed information about specific areas of relevance to OER.
By the Open Education Group. This review provides a summary of all known empirical research on the impacts of OER adoption and is periodically updated with new articles as the authors become aware of them.
From SPARC. This resource addresses seven common myths about OER.
How can OER impact students? They save students money!
Defining the "Open" in Open Content and Open Educational Resources - The 5 Rs
The terms "open content" and "open educational resources" describe any copyrightable work (traditionally excluding software, which is described by other terms like "open source") that is licensed in a manner that provides users with free and perpetual permission to engage in the 5R activities:
Source: Text and image by David Wiley, opencontent.org, published under a Creative Commons Attribution 4.0 license