RSA/DSA are the most common asmmetric ciphers (used in SSH and OpenSSL) Uses a pair of keys for encryption and decryption Encryption is accomplished with a public key Decryption can only be done with a private key Much slower than crypto hashes Still slower than most private (symmetric) key ciphers Tremendously useful for protecting data and Relatively easy to use Encrypting a message digest of a clear-text document Securing data entered into a database on an insecure server