What are the 5 branches of military? Different Military Branches - In simple terms, the U.S. Armed Forces are made up of the five armed service branches: Air Force, Army, Coast Guard, Marine Corps, and Navy. There are three general categories of military people: active duty (full-time soldiers and sailors), reserve & guard forces (usually work a civilian job, but can be called to full-time military duty), and veterans and retirees (past members of the military). The President of the United States is the Commander in Chief, who is responsible for all final military decisions. The Secretary of the Department of Defense has control over the military and each branch - except the Coast Guard, which is under the Dept. of Homeland Security. With over 2 million civilian and military employees, the Department of defense (DOD) is the world's largest "company." What are the differences between military branches? Each Service has a corresponding Reserve, and mos