Decrypted Secrets Methods and Maxims of Cryptology Wonderful Digest
1.1 Cryptography and SteganographyWe must distinguish between cryptography (Greek kryptos, hidden) and steganography (Greek steganos, covered). The term cryptographia, to mean secrecy in writing, was used in 1641 by John Wilkins, a founder with John Wallis of the Royal Society in London; the word ‘cryptography’ was coined in 1658 by Thomas Browne, a famous English physician and writer. It is the aim of cryptography to render a message incomprehensible to an un-authorized reader: ars occulte scribendi. One speaks of overt secret writing:overt in the sense of being obviously recognizable as secret writing.The term steganographia was also used in this sense by Caspar Schott, a pupil of Athanasius Kircher, in the title of his book Schola steganographia,published in Nuremberg in 1665; however, it had already been used by Trithemius in his first (and amply obscure) work Steganographia, which he began writing in 1499, to mean ‘hidden writing’. Its methods have the goal of concealing the very existence of a message (however that may be composed)—communicating without incurring suspicion (Francis Bacon, 1623: ars sine secreti latentis suspicione scribendi). By analogy, we can call this covert secret writing or indeed ‘steganography’.