Maths8 : Coding & Cyphers: Home

If you ever watched the movie The Imitation Game, you must be familiar with the word "Enigma". The Germans used this sophisticated cipher during the Second World War. It involved using an Enigma machine, which is similar to the type writer. All Germans had the same Enigma machine and the initial wheel configuration of the machine was communicated to all the teams. When a letter was pressed on the machine, a cipher letter lit up on the screen. It got even more difficult when the wheel rotated after certain number of letters, so that the cipher kept on changing. There could be over one hundred trillion possible configurations and hence was difficult to decipher Enigma.

Although it was difficult to decipher, during World War II, Alan Turing, a Cambridge University Mathematician, invented an electromechanical machine that could find settings for the Enigma machine and broke the Germany Enigma. His achievement shortened the war in Europe by 2 to 4 years. The Enigma code was also broken by the Polish. 

Source: http://www.enkivillage.com/types-of-codes.html

Imperial War Museums website - How Alan Turing cracked the Enigma code: https://www.iwm.org.uk/search/global?query=enigma

Listverse: http://listverse.com/2012/03/13/10-codes-and-ciphers/

This particular cipher was used during American Civil War and World War I to communicate sensitive messages. The letters of the alphabet are rearranged based on pre-determined key or rule. It could be that all the words in the message are written backwards, or every pair of letters is swapped. If the rearrangement rule is complex, it might seem very difficult to decipher, however, with modern algorithms on the computer, it can be easily deciphered. For example: “the yellow car belongs to him” can become “eht wolley rac sgnoleb ot mih” when written backwards.

Source: http://www.enkivillage.com/types-of-codes.html

ListVerse: http://listverse.com/2012/03/13/10-codes-and-ciphers/

In 1836, the American artist Samuel Morse, with the American physicist Joseph Henry, and Alfred Vail, developed an electrical telegraph system. Morse then developed the forerunner to modern International Morse code. The name "Morse code" is misleading because, this is in fact a cipher not a code. All the letters of the alphabet, number from 0-9 and some punctuation marks have been replaced by dots, dashes or short and long beeps. For example: A is "▪-". Morse code was popularly used when the telegraph was invented. Messages could be sent long-distance electrically using the Morse code via the telegraph. It was not used for concealing message, but transmitting information as a series of clicks, tones or lights.

A skilled observer or listener can directly understand the information without any equipment. It brought in a revolution, since updates from one country could be passed on to other countries immediately. Amateur radio operators used Morse code frequently. A basic understanding is required by pilots and air traffic controllers. SOS, the most common distress signal, recognized internationally is depicted as three dots, three dashes and three dots.

Source: http://www.enkivillage.com/types-of-codes.html

http://listverse.com/2012/03/13/10-codes-and-ciphers/

This particular cipher has been named after Julius Caesar, since he used it himself. A cipher was present for each letter of the alphabet, for example ROT1 is one of the ciphers. To decode the message, the person has to be aware which cipher has been used. In G cipher, A becomes G, B becomes H and so on. In Y Cipher, A becomes Y and so on. This particular cipher is not very difficult to decipher and hence secret messages do not remain secret for long. This particular cipher has been used as the basis for creation of more complex ciphers.

Source: http://www.enkivillage.com/types-of-codes.html

http://listverse.com/2012/03/13/10-codes-and-ciphers/