"OER 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 re-purposing by others. Open educational resources include full courses, course materials, modules, textbooks, streaming videos, tests, software, and any other tools, materials, or techniques used to support access to knowledge."
Definition taken from The William and Flora Hewlett Foundation
The 5 Rs of OER: The real power of OER comes in the “5R Permissions” that entitle you to not only access these materials free of charge, but also to make them better.
OER is a relatively new movement in education; educators and learners, as well as, learning institutions are driving its development. OER provides an alternative to the rising costs of education by offsetting the costs of textbooks and other learning materials. OER provides an opportunity to try new ways of teaching and learning, many of which are more collaborative and participatory.
Some educators are using OER as a way to get students more involved, using the OER process as a way to collaborate with them on content creation. This process brings students into a larger context of learning and sharing knowledge beyond the four walls of their classroom.
Flexibility is a key concept in OER. Materials can often be adapted for your specific needs. Because these materials can be searched by a wide variety of criteria, you can quickly find what you specifically need.