The M1 Abrams main battle tank is the principal combat tank of the United States Army and the United States Marine Corps, with three main versions being deployed starting in 1980: the M1, M1A1, and M1A2. The latest versions of the M1A2 have a new armor and electronics package. It is named after General Creighton Abrams, former Army Chief of Staff and commander of the Army's 37th Armored Regiment.
Military - Army
The M1 Abrams replaced the M60 Patton in U.S. service, as well as the M48A5. It did, however, serve alongside the M60A3, which had entered service just two years before the M1 (in 1978), for over a decade.