Open Educational 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.
Source: UNESCO
If you use content that resides in the public domain (currently anything published before 1924), there's no need to worry about copyright violations! The resources below can connect you to content in the public domain. To learn more about the timeline of works entering into the public domain, visit the Cornell University Library's Copyright Information Center.
