What are Creative Commons Licenses?
Creative Commons licenses give everyone from individual creators to large institutions a standardized way to grant the public permission to use their creative work under copyright law. From the reuser’s perspective, the presence of a Creative Commons license on a copyrighted work answers the question, What can I do with this work? - creativecommons.org
Below is a chart explaining the six different license types:
Creative Commons licenses by Foter (CC-BY-SA)