As soon as you put your ideas into a tangible form in the United States, that form is automatically copyrighted. Your blog. Your drawing. Your music. If you intend to let people use your work freely without having to ask your permission, you can apply a Creative Commons license to it. Not everyone wants to share freely in the same way, so there are a range of licenses. I've listed some of them below starting with the least restrictive. These symbols will tell you what the author has given you permission to do with their work.
Attribution: ShareAlike CC BY-SA
Attribution: NoDerivatives CC BY-ND
Attribution: NonCommercial CC BY-NC
Attribution: NonCommercial-ShareAlike CC BY-NC-SA
Attribution: NonCommercial-NoDerivatives CC BY-NC-ND
"Non-commercial" is self explanatory. "No Derivatives" means you can't alter or remix the material. "Share Alike" means that if you alter or remix their work, you must release it with the same license - not a more or less restrictive one. Questions? Click on the links above or ask me.
