a relatively small amount of information that is used by a cryptographic algorithm to 'customize' the transformation of plaintext into cyphertext (during encryption) or from cyphertext to plaintext (during decryption)
The session (symmetric) key used during the encryption and decryption processes, and the public and private keys used during the authentication process. Of these three keys, the session key and private key must always remain secret.
a binary number typically 40 to 128 bits long that an encryption algorithm uses to perform calculations. The greater the number of bits in the key (cipher strength), the more possible key combinations and the longer it would take to break the code.
A parameter that determines the transformation from plain text to cipher text or vice versa. For example a DEA key is a 64-bit parameter consisting of 56 independent bits and eight bits which may be used as odd parity bits.