When a work (such as a textbook) is created, it is protected by copyright. However, when the creator assigns an open license to their work, they are allowing others to use their work in certain ways. For open educational resources, Creative Commons (CC) licenses are the most used type of license. There are six types of Creative Commons licenses that specify how someone can use a specific work. In addition, works in the public domain are freely available to use.
What is Creative Commons?
Creative Commons is a nonprofit organization that enables the sharing and use of creative works through free legal tools.
Their free, easy-to-use copyright licenses provide a simple, standardized way for you to give the public permission to share and use your creative work — on conditions of your choice. Creative Commons (CC) licenses let you easily change your copyright terms from the default of “all rights reserved” to "some rights reserved."
Creative Commons licenses are not an alternative to copyright. They work alongside copyright and enable you to modify your copyright terms to best suit your needs.
Creative Commons Aotearoa New Zealand. (2019) Creative Commons Kiwi. Retrieved from https://www.youtube.com/watch?v=F0hh1FuMMmA
If video is does not work, copy and paste the following link into your browser: https://creativecommons.org/about/videos/creative-commons-kiwi/
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Types of Licenses
The Creative Commons organization has created pages explaining each license so that you can better understand how you can use a specific work in the public domain or one assigned a creative commons license.
Works in the public domain are the most open while copyrighted works are the least open. Works with one of the six Creative Commons licenses fall in between in terms of how open they are and how they can be used.
Image from Wikipedia: Creative Commons License