United Nations Organization for Education, Science and Culture (UNESCO) defines Open Educational Resources (OERs) as :
Any type of educational materials that are in the public domain or introduced with an open license. The nature of these open materials means that anyone can legally and freely copy, use, adapt and re-share them. OERs range from textbooks to curricula, syllabi, lecture notes, assignments, tests, projects, audio, video and animation.
OERs are licensed in such a way that enables adopters to utilize the 5 R permissions:
Retain a copy of the content
Reuse the content in a range of ways
Revise the content as needed
Remix original or revised content with other material
Redistribute the original, revisions, and remixes with others
Creative Commons licenses are often applied to OERs to license these rights to adopters.
Producers - OER allows educators the opportunity to design a custom textbook, course or any method of teaching to meet your classroom needs. Traditionally, the OER production workflow involves selecting, designing, developing, delivering and revising.
Consumers - Access to OER opens up a world of opportunities to anyone! By removing the financial barrier, OERs are accessible and promote education to anyone regardless of financial standing. OERs can provide students and parents with materials to support instruction and teaching outside of the traditional classroom or textbook models.