Creative Commons is a copyright license that is free to generate (no need to pay a lawyer!) that makes it easy for creative people to share their work on their own terms. Will you allow commercial use of your work? Will you allow your work to be modified? Do you require attribution? To create a CC license for your work, visit the Creative Commons site and answer a few questions, and your CC license will be automatically generated.
Creative Commons is not the same as Public Domain. Public Domain releases all rights to the public. Creative Commons allows the creator to hold some rights, such as not allowing commercial use, or not allowing the work to be modified, or requiring attribution.