North Vietnamese Army; aka Vietnam People's Army.
The NVA were the communists who fought against the Southern Vietnamese. Vo Nguyen Giap was one of it's most notable commanders.
U.S. military personnel whose job is to crawl through enemy tunnels in search of the Viet Congs.
The tunnel rats were American and Australian infantry soldiers whose task was to carry out underground search and destroy missions during the Vietnam War. The Viet Cong guerrillas had built a complex system of tunnels in which they hid themselves and their weapons when they were under attacks. They were extremely dangerous, with numerous booby traps and enemies lying in wait.
South Vietnamese Army; another name for the Army of the Republic of Vietnam (ARVN).
The South Vietnamese Army (SVA) had been financed by America throughout the late 1950’s, 1960’s and as a result of Vietnamization, to an even greater degree from 1970 to 1975.