An algorithm in which the key used for encryption is identical to the key used for decryption. DES is the best-known symmetric encryption algorithm.

A cryptographic algorithm that typically uses a single key, often referred to as a session key, for encryption and decryption. Symmetric algorithms can be divided into two categories, stream algorithms and block algorithms (also called stream and block ciphers).

Crypto algorithm that uses the same crypto key for encrypting and decrypting. Also called a " secret key" algorithm.

an encryption algorithm where the encryption key is the same as the decryption key, or where one key is easily calculated from the other. The sender and receiver have to agree on a key before they can communicate securely.

This is an encryption algorithm where the same key is used for both encryption and decryption (unlike asymmetric where different keys are used). The key used in a symmetric algorithm is often called a secret key because it has to be kept secret by all users of the system, unlike a public key that has to be made available to everyone.

An encryption in which the same secret key is used for both encryption and decryption.