 widely used in pre-computer ages for military communications (from the American Civil War to the First World War), for the early beginnings of the public telegraph, which, as true revolution of the time, brought the telegram, 8 and for maritime communications and safety. Today, its use is only restricted to nostalgic amateur groups. The Morse code is a binary-like or pseudo-binary code based on the two character values dit = and da = (or dot and dash, respectively). While anybody knows the meaning of SOS, fewer people know that it actually means "Save Our Souls," and maybe even fewer people know the Morse transcription: (dit dit dit/da da da/dit dit dit), as repeated several times. As symbolized above by the slash, each Morse codeword must in fact be separated by short pauses. Such pauses are meant for unambiguous identification of the codewords. This is because Morse messages are meant to be generated, to be written, and to be read in real time by human operators, and not by a machine. Table 8.2 shows the "Continental" international correspondence of the 44 Morse symbols with alphanumerical characters and various punctuation signs. The list is com- pleted with another five symbols for messaging commands. Note that there is no Morse symbol for "space," for consideration of economy. Morse messages make sense with- out spaces, just like HELLOHOWAREYOU or HAPPYBIRTHDAYTOYOU. It does not preclude that the sending operator may use the "wait" symbol once in a while, to take a breath or if he is accidentally interrupted whilst broadcasting a message. Yet full texts can be coded with all punctuation marks (except the exclamation point, !), which makes the Morse code very complete as a communication means. As one observes from Table 8.2, the shortest Morse symbols are attributed to the most common letters in The first telegram was sent from Baltimore to Washington, DC over electrical wires by Morse in 1844, see http://en.wikipedia.org/wiki/Electrical_telegraph. According to international maritime safety regulations, ship