The US Coast Guard, also known as the United States Coast Guard, is responsible for maritime safety, security, and protection of natural resources. Synonyms for the US Coast Guard include CG, United States Coastal Guard, USCG, Coasties, and the US Coastal Service. As an agency of the Department of Homeland Security, the US Coast Guard has been involved in various missions including search and rescue operations, law enforcement, and environmental response. The US Coast Guard is one of the five armed forces of the United States and is the only military organization that falls under the jurisdiction of the Department of Homeland Security.