Creative Commons licenses have become the gold standard of open licenses. There are now well over a billion items using Creative Commons licenses. This includes Open Access articles, with the majority of articles using CC-BY, and Open Educational Resources (OER). There are tens of millions of original videos on YouTube with a Creative Commons license, and hundreds of millions of images on Flikr. Creative Commons Licenses are most often used for items like, books, plays, movies, music, articles, photographs, blogs, and websites. Although one can use a Creative Commons License for software, because there is a well developed open licensing ecosystem for software, Creative Commons suggests using a license specifically designed for software.
Under the terms of the licenses, the copyright holders (licensors) still retain their copyrights and grant usage rights to the public (licensees). The licenses offer creators an array of choices with regards to the permissions they will grant to others.
For additional information about Creative Commons Licenses please see Hillary Fredette, Creative Commons and the CC licenses guide.