There are five service branches of the U.S. Armed Forces:
- U.S. Air Force (USAF)
- U.S. Army (USA)
- U.S. Coast Guard (USCG)
- U.S. Marine Corps (USMC)
- U.S. Navy (USN)
The Air Force is part of the Department of Defense (DOD). It’s responsible for aerial military operations, defending U.S. airspace and air bases, and building landing strips. The Air Force Space Command is under this branch. Service members are known as airmen. The reserve components are Air National Guard and Air Force Reserve.
The Army is part of the DOD and is the largest of the five military branches. It handles major ground combat missions, especially operations that are ongoing. The Army Special Forces unit is known as the Green Berets for its headgear. Service members are known as soldiers. The reserve components are Army Reserve and Army National Guard.
The Coast Guard is part of the Department of Homeland Security (DHS). It’s responsible for maritime law enforcement, including drug smuggling. It manages maritime search and rescue and marine environmental protection. It also secures ports, waterways, and the coasts. Service members are known as Coast Guardsmen, nicknamed Coasties. The reserve component is Coast Guard Reserve.
The Marine Corps is part of the DOD. It provides land combat, sea-based, and air-ground operations support for the other branches during a mission. This branch also guards U.S. embassies around the world and the classified documents in those buildings. Marine Corps Special Operations Command (MARSOC) members are known as Raiders. All service members are referred to as Marines. The reserve component is Marine Corps Reserve.
The Navy is part of the DOD. It protects waterways (sea and ocean) outside of the Coast Guard’s jurisdiction. Navy warships provide the runways for aircraft to land and take off when at sea. Navy SEALs (sea, air, and land) are the special operations force for this branch. All service members are known as sailors. The reserve component is Navy Reserve.