Open access is becoming a more common practice in the scholarly publishing world where authors and publishers make their works openly available to others. Open access works are freely shared, which in turn, increases their visibility by others in the research world.
Open Educational Resources - "freely accessible, openly licensed documents and media that are useful for teaching, learning, and assessing as well as for research purposes" Wikipedia. http://en.wikipedia.org/wiki/Open_educational_resources
Open-Access Scholarly Literature - This is academic publication available online for free. Most of the copyright and licensing material does not have restrictions. This site lists over 9,000 peer-reviewed, open access journals. https://doaj.org/
Open Source Software Licenses - Allow software to be freely used, modified, and shared. https://opensource.org/licenses