steganography
Hiding a secret message within a larger one in such
a way that others can not discern the presence or contents of
the hidden message. For example, a message might be hidden
within an {image} by changing the {least significant bits} to
be the message bits.
[{Chaffing and Winnowing: Confidentiality without Encryption,
Ronald L. Rivest, MIT Lab for Computer Science, 1998-03-22
(http://theory.lcs.mit.edu/~rivest/chaffing.txt)}].
(1998-07-13)