Creative Commons licenses are a kind of knowledge protection related to culture, scientific and educational work that as copyright are based on the intellectual property rules.
These type of licenses are issued by the global Creative Commons project in a standardised license model, designed to provide the author with the ability to authorize, under certain conditions, the use and exploitation of a published work on the Internet.
There are different types of licenses that allow reproduction, distribution, transformation and public work communication for any purpose and for all forms of exploitation, free of charge and for the entire term of protection.
More information: Creative Commons