The Creative Commons licenses (http://us.creativecommons.org/) make it easier for authors and users to share and use copyrighted works without seeking prior permission from the copyright owner.
Creative Commons licenses do not alter the copyright status of a work, instead they permit specific uses as defined by the copyright owner and all users know what rights the copyright owner is allowing.
For example CC licenses may allow “free and open use with attribution to the creator” (Figure 1) or place some caveats around use, such as reuse must be "attributed to the creator, can only be for for non-commercial uses, and the rights assigned to the derivative work must be the same as those on the original work" (Figure 2).
|Figure 1.||Figure 2.|
See the grid of available Creative Commons licenses: http://creativecommons.org/licenses/