Introduction to Steganography
"Steganography is the art and science of communicating
in a way which hides the existence of the communication.
In contrast to cryptography, where the enemy is allowed to
detect, intercept and modify messages without being able
to violate certain security premises guaranteed by a crypto-
system, the goal of steganography is to hide messages inside
other harmless messages in a way that does not allow any
enemy to even detect that there is a second secret message present.”
[Markus Kuhn 1995-07-03].