United States Navy : United States Marine Corps (USMC)
Website:
http://www.marines.com/ The mission of the Navy is to maintain, train and equip combat-ready Naval forces capable of winning wars, deterring aggression and maintaining freedom of the seas.
United States Marine Corps (USMC) is a branch of the United States armed forces responsible for providing force projection from the sea and is a component of the Department of the Navy, working closely with US Naval forces for training, transportation, and logistic purposes.
Marines can serve on active duty and in the Marine Corps Reserve, as both  enlisted Marines and officers.