The formal delivery of notice of a legal document to insure the opposing party is aware of the action and is given an opportunity to respond to it. “Personal service” means the actual delivery to the person to whom it is directed and is usually required for the initiation of most lawsuits. “Substitute service,” where notice is given by other means such as publication in a legal notice or provision of the documents to the Secretary of State, is allowed under certain limited circumstances, usually when a defendant’s whereabouts are unknown.