secret codes
Encrypted communication systems
Secret codes are systems for concealing meaning from unintended audiences—letters, numbers, or symbols standing for other letters, numbers, or words.
Children pass notes in secret codes; spies use them for sensitive communications.
The term often implies something breakable with ingenuity, unlike modern encryption: We made up a secret code where each letter shifted three places.
Figuratively, understanding someone's secret code means grasping their hidden logic or unstated rules.
- Vigenère cipherEncryption using repeating keyword
- cipherHidden writing system
- Enigma machineElectromechanical encryption device
- keyLock-opening device
- cryptogramsEncoded text puzzles
codebooks · Caesar cipher · codebreaking · decryption · cryptanalysis · Morse code · steganography · code name · invisible ink · dead drop · decoder ring · coded messages · hidden meaning · cracked · intercept · scrambled · transmission · classified
- spy gearspy gadgets, decoder rings, invisible ink, microfilm, silencers
- Codebreakingcodebreakers, codebreaking, cryptanalysis, cipher, ciphers
- game cheatscheats, invincibility, infinite lives, infinite health, unlimited ammo
- Hidden Meaningssubtext, hidden meaning, coded messages, cipher, implied meaning
- espionagespy, spies, double agent, double agents, spying
- secrecy in literaturemystery, secrets, spies, espionage, spy novels
secret codesplain language
Easily understood communication
plaintext · cleartext · open communication · plain English · public announcements
secret codespublic knowledge
Facts anyone can access
common parlance · universal language · public domain · open channels · public broadcast