Cryptography and Cryptanalysis: Key Concepts and Definitions

Plaintext

the original message

Ciphertext

the coded/encrypted message

Cipher

algorithm that turns plaintext into ciphertext

Key

secret info used by the cipher (known only to sender/receiver)

Encipher (Encrypt)

convert plaintext → ciphertext

Decipher (Decrypt)

recover plaintext from ciphertext

Cryptography

study of how to encrypt (methods/principles)

Cryptanalysis

codebreaking: decipher ciphertext without the key

Cryptology

cryptography + cryptanalysis together