Creative Commons licenses are an alternative to traditional copyright.
Creative Commons is a non-profit organization created to address the problem that arises when copyright laws created to cover non-digital media are forced to cover digital media, which explicitly relies on copying to function.
"The idea of universal access to research, education, and culture is made possible by the Internet, but our legal and social systems don’t always allow that idea to be realized. Copyright was created long before the emergence of the Internet, and can make it hard to legally perform actions we take for granted on the network: copy, paste, edit source, and post to the Web. The default setting of copyright law requires all of these actions to have explicit permission, granted in advance, whether you’re an artist, teacher, scientist, librarian, policymaker, or just a regular user. To achieve the vision of universal access, someone needed to provide a free, public, and standardized infrastructure that creates a balance between the reality of the Internet and the reality of copyright laws. That someone is Creative Commons."
You might also want to check out this short video to learn more about Creative Commons.