A registered agent is a person designated to officially receive and send legal papers on behalf of a business entity, such as a limited liability company (LLC) or a corporation. The registered agent is registered with the state in which the LLC or corporation is established. The articles of organization (for an LLC_) or the articles of incorporation (for a corporation) must designate the registered agent, along with an address (not a post office box).
The registered agent is the person who receives official notifications, including notice of lawsuits and state taxes due. If you are running a very small business, you can be your own registered agent. If one or more individuals are running a business together, one person is usually designated as the registered agent.
Check with the office of your state Secretary of State for more information.