100 P ALLEY: A Five or Six block long street just outside the main gate of Tan Son Nhut Air Base in Saigon where you could buy just about anything and where all the prostitutes hung out.
101st: The U.S. Army's 101st Airborne Division, aka "The Screaming Eagles. During the Vietnam War, the 101st Airborne Division was redesignated first an Airmobile Division, then later as an Air Assault Division. It is the only U.S. Army division with two aviation brigades. It is one of the most prestigious and decorated divisions in the U.S. Army.
105: A 105-mm howitzer.
11-Bravo: Army designation for an infantryman.
122mm, 140mm, ETC.: Large-caliber enemy rockets.
2.75: Diameter of the side (pod) mounted rockets carried on all older "D" model Huey gunships and the newer Cobras.
201 file: A U.S. Army personnel file.
4-F: Classification given to those deemed unfit for military service.
50-cal: .50 caliber machine gun.
51-cal: Heavy machine gun used by the enemy.
7.62 MINIS: The AK-47; refers to the caliber bullet the AK used.
79: An M-79 grenade launcher.
82 mm: A mortar used by the enemy
