SECRET - List of Coded Words National WWI Museum and Memorial

The military has used codes and ciphers for years, but the use and complexity of codes skyrocketed during World War I.

Gone But Not Forgotten – Part 4: Sergeant Morton Ralph Heinish and the Second World War

Secret codes hi-res stock photography and images - Alamy

UK spy agency releases Xmas puzzle: Can you solve it?

Navajo Code Talkers – The Unwritten Record

Why Keep That? National WWI Museum and Memorial

What are some examples of secret codes used in WWI and WWII? - Quora

SECRET - List of Coded Words National WWI Museum and Memorial

Apocalypse-Proof

War of Secrets: Cryptology in WWII > National Museum of the United States Air Force™ > Display

Zimmermann Telegram National WWI Museum and Memorial

SECRET - List of Coded Words National WWI Museum and Memorial