Believe it or not, a person does not have to register a copyright for a work to be copyrighted. Since 1978, when copyright law was massively changed, if you create something, it's copyrighted. That said, if you create something that you feel will generate a potential profit or something you want the world to know you created, you should register your work. Registering your work serves to create a record which shows who owns the rights. It's the essential safeguard.