Open Education Resources (OER) 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."
OERs were born from the Open Education movement, which seeks to use the technological tools of the Internet to make knowledge and learning affordable and globally accessible. Examples of material formats released as OERs include but are not limited to online courses, textbooks, videos, tutorials, lectures, syllabi, tests, blogs, and wikis.