CC Licenses
Creative Commons is an American non-profit organization that supports people to grow and sustain the commons of shared knowledge and culture.
The organization has released several copyright licenses, known as Creative Commons licenses, free of charge to the public. These licenses allow authors of creative works to communicate which rights they reserve and which rights they disclaim for the benefit of recipients or other creators. Creative Commons licenses give standard releases that replace the individual negotiations for specific rights between the copyright owner (licensor) and licensee, which are necessary under an “all rights reserved” copyright management. At the same time, content owners still maintain their copyright.
Six regularly used licenses:
You can read more about licenses – Creative Commons – Licenses List