substitution cipher
Alphabet replacement system
A substitution cipher is a method of encryption where each letter or symbol in a message is replaced by another according to a fixed system.
The simplest form replaces each letter with a different letter: A becomes X, B becomes Q, and so on.
The children passed notes in a substitution cipher they'd invented.
Crossword puzzles called cryptograms use simple substitution ciphers as their basis.
Converting data into code
- ciphertextEncoded, unreadable message
- plaintextUnencoded readable information
- keyLock-opening device
- alphabetLanguage's letter system
encoding · decoding · scramble · permutation · cryptogram · codebook · secret writing
Coded message puzzle
- brainteaserPuzzle demanding clever thought
- wordplayVerbal wit techniques
- challengeTest of ability
- solverOne who finds solutions
clue · word game · logic · deduction · hint · puzzle book · recreational
Identifying regularities in inputs
- codebreakingSolving secret communications
- decryptionConverting ciphertext to plaintext
- n-gramsContiguous linguistic subsequences
- bigramsTwo-letter sequences
trigrams · cryptanalyst · solving · breaking · crib · statistical analysis · vulnerability · brute force
Act of hiding something
- hidden messageCovert communication within another
- covertIntentionally concealed
- confidentialMeant to stay secret
- clandestineConcealed from authorities
disguise · obfuscation · steganography · invisible ink · spy · intelligence · private · coded message
Roman imperial title
- Julius CaesarRoman dictator and general
- ancient RomeEarly Italian empire city
- SpartansCitizens of ancient Laconia
- medievalOf the Middle Ages
Mary Queen of Scots · Edgar Allan Poe · Sherlock Holmes · espionage
encryption
Converting data into code
- ciphertextEncoded, unreadable message
- plaintextUnencoded readable information
- keyLock-opening device
alphabet · encoding · decoding · scramble · permutation · cryptogram · codebook · secret writing
cryptogram
Coded message puzzle
- brainteaserPuzzle demanding clever thought
- wordplayVerbal wit techniques
- challengeTest of ability
solver · clue · word game · logic · deduction · hint · puzzle book · recreational
pattern recognition
Identifying regularities in inputs
- codebreakingSolving secret communications
- decryptionConverting ciphertext to plaintext
- n-gramsContiguous linguistic subsequences
bigrams · trigrams · cryptanalyst · solving · breaking · crib · statistical analysis · vulnerability · brute force · attack
concealment
Act of hiding something
- hidden messageCovert communication within another
- covertIntentionally concealed
- confidentialMeant to stay secret
clandestine · disguise · obfuscation · steganography · invisible ink · spy · intelligence · private · coded message · secure communication
Caesar
Roman imperial title
- Julius CaesarRoman dictator and general
- ancient RomeEarly Italian empire city
- SpartansCitizens of ancient Laconia
Mary Queen of Scots · Edgar Allan Poe · Sherlock Holmes · medieval · espionage
- codes and cipherscode, decode, decrypt, encrypt, ciphertext
- cryptic puzzlesriddle, code, cryptogram, enigma, puzzle
- secret codessecret code, secret codes, code word, password, passphrase
- secret messagecode, invisible ink, cryptogram, Morse code, number code
- ciphersciphertext, plaintext, Enigma machine, encryption key, decryption
- code booksnaval code, military code, commercial code, radio code, secret code
substitution cipherplaintext
Unencoded readable information
cleartext · decryption · decipherment · cryptanalysis · open communication
substitute, cipher, substitution, substituted, substitutes, substituting, ciphering