Copyrights protect the way in which original works of authorship are expressed. Owners have the exclusive right to copy, perform, and distribute their works. Copyright protection is not available for the actual idea; it is available for the way the idea is expressed. So while you can’t copyright the idea of a time-traveling car, you can copyright a story based on the idea. And apparently, you can’t copyright what a tattoo stands for, but you can copyright the actual expression of the idea on someone’s face.
Besides the relative ease of online registration, entrepreneurs should register their copyrights for another reason: it is required before one can sue for damages as a result of infringement.
Copyright protection is limited. It is usually limited to the life of the author plus 70 years. For works made for hire, the length of protection is 95 years from the year of first publication or 120 years from its creation, whichever expires first.