Tap Code
The tap code, which is said to date back as early as the Korean War, is a method of communication that was used in a North Vietnamese POW camp known to American soldiers as the "Hanoi Hilton".
It is a simple transmission system that uses a series of taps to convey a coded message. The sender references a chart and taps on a wall, floor, or pipe to distribute their code, which the receiver must then decipher.
This allowed prisoners of war to exchange information without speaking to each other.
The code is arranged on a grid. The first set of taps defines which row the letter or number is in (1 tap for the first row, 2 for the second, etc.). After a short pause, a second set of taps defines the column.
It is a simple transmission system that uses a series of taps to convey a coded message. The sender references a chart and taps on a wall, floor, or pipe to distribute their code, which the receiver must then decipher.
This allowed prisoners of war to exchange information without speaking to each other.
The code is arranged on a grid. The first set of taps defines which row the letter or number is in (1 tap for the first row, 2 for the second, etc.). After a short pause, a second set of taps defines the column.
