OER and OA materials generally use the following icons to indicate any restrictions or requirements for their use:
Creative Commons
BY: Credit must be given to the creator.
NC: Only non-commercial uses of the work are permitted.
ND: No derivatives or adaptations of the work are permitted.
Public Domain Mark: Allowed to distribute, remix, adapt, and build upon the material in any medium or format.
SA: Adaptations must be shared under the same terms as the original.
CC0:(aka CC Zero) is a public dedication tool, which allows creators to give up their copyright and put their works into the worldwide public domain. CC0 allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, with no conditions.
Understanding Licensing
Creative Commons Licenses are generally shown on OER resources to allow the user to see what restrictions, if any, there may be for using the work. These licenses include:
CC BY: This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. The license allows for commercial use.
CC BY includes the following elements:
BY 
– Credit must be given to the creator
CC BY-SA: This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. The license allows for commercial use. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.
CC BY-SA includes the following elements:
BY – Credit must be given to the creator
SA 
– Adaptations must be shared under the same terms
CC BY-NC: This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format for noncommercial purposes only, and only so long as attribution is given to the creator.
It includes the following elements:
BY – Credit must be given to the creator
NC 
– Only noncommercial uses of the work are permitted
CC BY-NC-SA: This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format for noncommercial purposes only, and only so long as attribution is given to the creator. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.
CC BY-NC-SA includes the following elements:
BY – Credit must be given to the creator
NC – Only noncommercial uses of the work are permitted
SA – Adaptations must be shared under the same terms
CC BY-ND: This license allows reusers to copy and distribute the material in any medium or format in unadapted form only, and only so long as attribution is given to the creator. The license allows for commercial use.
CC BY-ND includes the following elements:
BY – Credit must be given to the creator
ND 
– No derivatives or adaptations of the work are permitted
CC BY-NC-ND: This license allows reusers to copy and distribute the material in any medium or format in unadapted form only, for noncommercial purposes only, and only so long as attribution is given to the creator.
CC BY-NC-ND includes the following elements:
BY – Credit must be given to the creator
NC – Only noncommercial uses of the work are permitted
ND – No derivatives or adaptations of the work are permitted
CC0 (aka CC Zero) is a public dedication tool, which allows creators to give up their copyright and put their works into the worldwide public domain. CC0 allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, with no conditions.
License images, icons, and descriptions retrieved and derived from Creative Commons (https://creativecommons.org/about/cclicenses/)