101 - Part 1
The ancient Greeks were the first people use means of concealing
messages. While their methods cannot be classified as cryptography,
because they did not change the written message to make it appear
as nonsense, these ancients took the first step at evolving
the ancient art.
The ancient Greeks used steganography to conceal messages
from prying eyes. Steganography comes from the Greek meaning
"covered or hidden writing." It is the art and science
of writing a hidden message that only the sender and receiver
can read. The ancient art traces back to 440 B.C. The famous
historian Herodotus mentions two cases in his Histories.
In the Histories Herodotus mentions Histiaeus, a king
taken out of power by the Persians. Wishing to return to power,
he sent a hidden message telling his people to revolt against
the foreign occupation. Since the Persians controlled the
region, then certainly any message of rebellion would be discovered
if sent by messenger?
To hide his message Histiaeus shaved the head of his most
trusted slave and tattooed his message onto the slave's head.
When the slave's hair regrew the king sent the slave to deliver
the message. When he arrived he shaved his head revealing
the King's message.
He also tells the story of Demaratus, King of Sparta, who
sent a message to Greece about the forthcoming attack by writing
it on a wooden panel and covering it with wax. Wax tablets
were used in that time as reusable writing surfaces, so no
treachery was suspected. When the tablets reached their destination
the wax was melted revealing the hidden message.
Generally a steganographic message will appear to be something
else like a picture, an article, a grocery list etc. The advantage
is that the hidden message does not draw attention to the
sender or receiver, as a mass of jumbled letters will immediately
Continue to Methods of Concealment