Public (Asymmetric) Key Encryption

Public key cryptography uses key pairs, a public key and a mathematically related private key. Given the public key, it is infeasible to find the private key. The private key is kept secret while the public key may be shared with others. A message encrypted with the public key can only be decrypted with the private key. A message can be digitally signed with the private key, and anyone can verify the signature with the public key.