Creative Commons is used by creators to allow various levels of use...effectively loosening traditional copyright protection.
The following are the levels of Creative Copyright permissions allowed.
Creative Commons Licenses
Attribution (CC BY)
the least restrictive license allowing for others to share and adapt the content freely as long as attribution is provided to the original work, link to the license and statement of changes made to the original content.
Attribution-NonCommercial (CC BY-NC)
Allows others to share and adapt the content freely but only for non-commercial use. Attribution must be provided to the original work, link to the license and statement of changes made to the original content.
Attribution-NoDerivs (CC BY-ND)
Allows others to share and adapt the content both commercially and non-commercially, but not to adapt the content or create derivatives. Attribution must be provided to the original work, link to the license and statement of changes made to the original content.
Attribution-ShareAlike (CC BY-SA)
Allows others to share and adapt the content both commercially and non-commercially, but if content is changed or adapted, the users must use the same license for the new material as was used for the original work. Attribution must be provided to the original work, link to the license and statement of changes made to the original content.
Allows others to share and adapt the content but only for non-commercial use. If content is changed or adapted, the users must use the same license for the new material as was used for original work. Attribution must be provided to the original work, link to the license and statement of changes made to the original content.
Attribution-NonCommercial-NoDerivs (CC BY-NC-ND)
the most restrictive license allowing others to share only and for non-commercial use only. No adaptation or creating derivatives are allowed. Attribution must be provided to the original work with link to the license.
Public Domain (CC0)
Allows others to use the original work without restrictions.
Some Misconceptions About Copyright and Open Access
Free Access
Free access does not mean that the work is free of all copyright conditions.
No Copyright Statement Visible
The absence of a copyright statement or copyright icon does not mean that the work is in public domain and free of some copyright.