From the Riddles of Ancient Egypt to Cryptography in the Renaissance — 3500 Years in the Making - Codes: The Guide to Secrecy from Ancient to Modern Times - page 3

Figure 1.2: Phaistos disk.
(In the above figure, the A side is on the left, and the B side on the right.)
Earlier we made some references to Greek mythology. There are other
references in this type of myth to cryptography : the study of methods for
sending messages in secret, which we now understand to mean the study of
methods for transforming of plaintext into ciphertext. (The word “cryptog-
raphy” comes from the Greek kryptos meaning hidden and graphein , mean-
ing to write .) We will learn a lot more about the cryptographic anecdotes
in Greek mythology in Section 1.2. For now, this is a convenient juncture
to introduce some terms related to cryptography, and discuss their origins.
Cryptanalysis is the study of methods for defeating cryptography. The ety-
Figure 1.3: Phaistos royal apartments.