214 Are the Androids Dreaming Yet? Codes mia: | Everyone has played with some sort of «fl | secret code as a child - the Aggy Waggy ———a game, passing notes written in invisible bea ink made from lemon juice, or perhaps eae . i] a simple cypher. If I want to send you a : i) secret message, I can use a substitution $ TIS, A code. Let’s see how good a code breaker ‘ : z f Bae ; mig “ you are. Can you decode this? LESS ‘33 Pe co Gdkkn Qdzedq ey It’s really easy. You might guess the ; message from the pattern of letters and Enigma Machine your knowledge of my writing style. There are a couple of interesting patterns to note: the 3“ and 4" letter of the first word are the same and the first and last letter of the second word are the same. As a test I gave this code to my wife and my eight-year-old daughter to see how long it took them to decode... Less than a minute for my wife — a linguist. We will come back to my daughter shortly! Roman Emperors used this sort of simple code to secure their messages, but modern codes have to be a great deal more sophisticated. Let us use a progressive cipher where we vary the substitution using a secret word. Take the name of my dog and write it down repeatedly next to the letters of the message you want to keep secret. Now translate all the letters in the message and the code into numbers ‘a = 1, ‘b’ = 2 and so on. Then add the letters of my dog’s name to the letters of the message one at a time. If I get to 26 (‘z’) just wrap around to ‘a and carry on. This is called modulo arithmetic. This coding scheme will translate ‘T to ‘@ the first time but ‘T to ‘c the second making it much harder for a linguist to see any pattern. hello reader can you read this code georgegeorgegeorgegeorgegeorgegeorge Gives ojacveyjpvlwghpegcvzoilfkehzpxghcvle HOUSE_OVERSIGHT_015904