A Cipher (or cypher) is an algorithm
for performing Encryption
Cipher that uses the same key to both Encryption and Decryption is a symmetric cipher.
asymmetric ciphers use a different keys for Encryption and Decryption. Typically we use a Private Key for Encryption and a Public Key for Decryption.
Ciphers are one of:
A Cipher uses a key
and transforms a Plaintext message
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