Key In encryption, a key is a specific value known exclusively by the parties concerned in the encrypted communication. Using an algorithm, the key is applied in order to encrypt and decrypt data.
The key length, specified in bits, describes the strength of the encryption. A 128-bit key is thus stronger than e.g. a 32-bit key. Keys are used in symmetric (a.k.a. secret key) encryption as well as in asymmetric (a.k.a. public key) encryption.
