Cryptography is the art of en- and decryption. Complex mathematical algorithms hide the meaning of information, saving it from unauthorised access.

The histories of language, communication and cryptography have always been connected to one other. The first elements of cryptography date back to the 20th century BC, in hieroglyphic inscriptions. It was then that the eternal war between enciphering and deciphering started. Occupying the delicate dividing line between the public and private realms, cryptography has traditionally been used for political and military purposes, as in the case of the German Enigma machine used during WW II.

But encryption has also become an important tool for private communications. In 1991 PGP (= Pretty Good Privacy) was released as freeware on the Internet by Phil Zimmermann.
Encryption became a public good.