"What is ZTC?" (54 seconds) is by Evelyn & Howard Boroughs Library
"Open Educational Resources (OER) are learning, teaching and research materials in any format and medium that reside in the public domain or are under copyright that have been released under an open license, that permit no-cost access, re-use, re-purpose, adaptation and redistribution by others" (UNESCO).
As outlined by Wiley, true OER allow for the following 5R's:
OERs can include full books, courses, lesson plans, activities, test banks, PowerPoint presentations, and more.
"What is OER?" (1 minute & 39 seconds) by The Council of Chief State School Officers is licensed under CC BY-NC 4.0
Unlimited licenses were specifically purchased for these books being used in classes in Fall 2023:
"Open Access [OA] is the free, immediate, online availability of research articles combined with the rights to use these articles fully in the digital environment. Open Access is the needed modern update for the communication of research that fully utilizes the Internet for what it was originally built to do—accelerate research" (SPARC). This movement has also extended into academic books. Wikipedia's "Open Access" entry is quite good and explains the nuances related to OA and OA practices.
Open access content is sometimes designated by the unlocked orange lock icon. The OA logo was originally designed by Public Library of Science. Some of the library's databases do include OA content. The library's OneSearch catalog allows you to specifically search for OA materials.
"Open Access" (2 minutes & 21 seconds) by PfauLibrary is licensed under CC BY 3.0
The following is from "Welcome to Public Domain" by Stanford Libraries, which is licensed under CC BY-NC 3.0:
The term “public domain” refers to creative materials that are not protected by intellectual property laws such as copyright, trademark, or patent laws. The public owns these works, not an individual author or artist. Anyone can use a public domain work without obtaining permission, but no one can ever own it.
There are four common ways that works arrive in the public domain:
The Copyright Services guide by Cornell University Library, which is licensed under CC BY 4.0, also contains a helpful section related to the public domain.
"What is Public Domain?" (3 minutes & 24 seconds) is by the U.S. Copyright Office