Public Key Cryptography
Public Key Cryptography is form of cryptography first published in 1976 by Martin Hellman and Whitfield Diffie which has a public and private key. A public key is one half of a software asymmetric cryptographic system that can secure messages for transmission over an open or non-secure network between two parties. The public key can be viewed or used by anyone, but the private key is kept secret by the creator and is the only method of decrypting the data encrypted by the public key.
The sender uses the recipient's public key to encrypt the message, sends the message, and once received, the recipient decrypts the message with his or her private key. The recipient's public key must be known, and this is done through the use of a central available to all participants.