Privacy: Information must be kept from unauthorized parties

Privacy is handled by encryption. In PKI (public key infrastructure) a message is encrypted by a public key, and decrypted by a private key. The public key is widely distributed, but only the recipient has the private key. For authentication (proving the identity of the sender, since only the sender has the particular key) the encrypted message is encrypted again, but this time with a private key. Such procedures form the basis of RSA (used by banks and governments) and PGP (Pretty Good Privacy, used to encrypt emails).

As we all know, all of the informations can be found in the internet. Even this public key infrastructure or PKI is not safe enough to accommodate certain transactions in the internet. But even if that's the case, still it is one of the privileges that new technologies bring to the society. We cannot take it away easily because it is the new trend in doing business nowadays. It is very convenient especially to large-scale businessmen to transact businesses only by just merely sitting in a cafe. It is just in the businessmen's hands on how to keep their privacy properly. After all, informations must be kept from unauthorized parties.