| 
    Introduction "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.  | 
| 
     | 
| 
    The 19th Century: Machine-Assisted Manufacturing Eli Whitney's proposal for a simplification and standardization of component parts marked a further milestone in the advance of the By the middle of the 19th century the general concepts of  | 
| 
     | 
| 
    1000 B.C. - 0 900 B.C. A postal service is used for governmental purposes in China. 500 B.C. In ancient Greece trumpets, drums, shouting, beacon, fires, smoke signals, and mirrors are used for message transmission. 4th century B.C. Aeneas Tacitus, a Greek military scientist and cryptographer, invented an optical communication system that combines water and beacon telegraphy. Torches indicated the beginnings and the ends of a message transmission while water jars were used to transmit the messages. These jars had a plugged standard-size hole drilled on the bottom side and were filled with water. As those who sent and those who received the message unplugged the jars simultaneously, the water drained out. Because the transmitted messages corresponded to water levels, the sender indicated by a torch signal that the appropriate water level had been reached. The methods disadvantage was that the possible messages were restricted to a given code, but as the system was mainly used for military purposes, this was offset by the advantage that it was almost impossible for outsiders to understand the messages unless they possessed the codebook. With communication separated from transportation, the distant became near. Tacitus' telegraph system was very fast and not excelled until For further information see Joanne Chang & Anna Soellner, Decoding Device, 3rd century B.C. Wax tablets are used as writing material in Mesopotamia, ancient Greece, and Etruria. 2nd century B.C. In China paper is invented. 1st century B.C. The use of codices instead of scrolls - basically the hardcover book as we know it today - is an essential event in European history. To quote accurately by page number, to browse through pages and to skip chapters - things that were impossible when reading scrolls - becomes possible. In the computer age we are witnesses to a kind of revival of the scrolls as we scroll up and down a document. The introduction of hypertext possibly marks the beginning of a similar change as has taken place with the substitution of scrolls with codices.  | 
| 
     | 
| 
    Content Choice and Selective Reporting Media as today's main information sources unarguably have the power to influence political agenda-setting and public opinion. They decide which topics and issues are covered and how they are reported. Still, in many cases those decisions are not primarily determined by journalistic criteria, but affected by external factors. The importance of shareholders forces media to generate more profit every quarter, which can chiefly be raised by enlarging audiences and hence attracting more advertising money. Therefore the focus of media's programming in many cases shifts towards audience alluring content like entertainment, talk-shows, music and sports. Further pressure regarding the selection of content occurs from advertisers and marketers, who often implicitly or explicitly suggest to refrain from programming which could show them or their products and services (e.g. tobacco) in an unfavorable light. Interlocking directorships and outright ownerships can moreover be responsible for a selective coverage. Financial connections with defense, banking, insurance, gas, oil, and nuclear power, repeatedly lead (commercial) media to the withholding of information, which could offend their corporate partners. In totalitarian regimes also pressure from political elites may be a reason for the suppression or alteration of certain facts.  | 
| 
     | 
| 
              Robot Robot relates to any automatically operated machine that replaces human effort, though it may not resemble human beings in appearance or perform functions in a humanlike manner. The term is derived from the Czech word robota, meaning "forced labor." Modern use of the term stems from the play R.U.R., written in 1920 by the Czech author Karel Capek, which depicts society as having become dependent on mechanical workers called robots that are capable of doing any kind of mental or physical work. Modern robot devices descend through two distinct lines of development--the early  | 
| 
     | 
| 
              Framing Framing is the practice of creating a frame or window within a web page where the content of a different web page can be display. Usually when a link is clicked on, the new web page is presented with the reminders of the originating page.  | 
| 
     | 
| 
              Electronic Data Interchange (EDI) EDI is an international standard relating to the exchange of trade goods and services. It enables trading partners to conduct routine business transactions, such as purchase orders, invoices and shipping notices independent of the computer platform used by the trading partners. Standardization by EDI translation software assures the correct interpretation of data. EDI might become increasingly important to electronic commerce.  | 
| 
     | 
| 
              skytale The skytale (pronunciation: ski-ta-le) was a Spartan tool for encryption. It consisted of a piece of wood and a leather-strip. Any communicating party needed exactly the same size wooden stick. The secret message was written on the leather-strip that was wound around the wood, unwound again and sent to the recipient by a messenger. The recipient would rewound the leather and by doing this enciphering the message.  | 
| 
     | 
| 
              File Transfer Protocol (FTP) FTP enables the transfer of files (text, image, video, sound) to and from other remote computers connected to the Internet.  | 
| 
     |