"A man is crazy who writes a secrete
in any other way than one which
will conceal it from the vulgar."
Roger Bacon (~1250 AD)
The essence of human communication is not only the social behavior to give or get messages (of whatever meaning) but also how to give and get them, and to include certain people by excluding others from the process of informing.
e.g. whispering is an effective way of talking to exclude the majority.
What about ways of writing?
Already some of the first written messages in human history obviously found special forms of hiding contents from the so-called others. When the knowledge of writing meant a privilege in a stronger sense as it is true today (in China for a long period writing was forbidden to people not working for the government), the alphabet itself was a kind of cryptography (that is why Catholic churches were painted with pictures explaining the stories of the Bible).
Certainly the methods of deciphering and enciphering improved a lot during the last 4.000 years. In the meantime cryptography has become a topic without end and with less technological limits every day. On the one hand there is the field of biometrics, which is highly related to cryptography but still in its beginnings, on the other hand there emerge so-called infowars, which intend to substitute or at least accompany war and are unthinkable without cryptography.
But there is much more to detect, like the different forms of de- and encoding. And very important, too, there is the history of cryptography that tells us about the basics to make it easier to understand today's issues.
In the actual age of (dis-)information storing and transporting electronic information safely increases its importance. Governments, institutions, economy and individuals rely on the hope that no-one can read or falsify their messages/data as it is much more difficult to detect and proof abuses in electronic media than in elder forms of written communication.
TEXTBLOCK 1/1 // URL: http://world-information.org/wio/infostructure/100437611776/100438658802
This book gives a fascinating glimpse of the many documented attempts throughout history to develop effective means for long distance communications. Large-scale communication networks are not a twentieth-century phenomenon. The oldest attempts date back to millennia before Christ and include ingenious uses of homing pigeons, mirrors, flags, torches, and beacons. The first true nationwide data networks, however, were being built almost two hundred years ago. At the turn of the 18th century, well before the electromagnetic telegraph was invented, many countries in Europe already had fully operational data communications systems with altogether close to one thousand network stations. The book shows how the so-called information revolution started in 1794, with the design and construction of the first true telegraph network in France, Chappe's fixed optical network.
http://www.it.kth.se/docs/early_net/