The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined.
The U.S. Navy traces its roots back to the Continental Navy, which was created during the American Revolution, and was abolished shortly after. During the presidency of Thomas Jefferson, the U.S. Navy was established in response to the problem of the Barbary Coast pirates. Since then, the U.S. Navy has been critical in nearly all of America's wars.