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 or re-purposing by others. OER include textbooks, course materials, streaming videos, tests, modules, full courses, software, and any other tools, materials or techniques used to support access to knowledge.
OER is a relatively new movement in education; educators and learners as well as learning institutions are driving its development. Open textbooks, a subset of OER, can help improve the learning experience for students while also making education more affordable.