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  Two Dutch Naval officers invented a machine to encrypt messages. This became known as the Enigma machine.
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  Arthur Scherbius, a German businessman, patented the Enigma machine.
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  Mass production of Enigma machine with 30,000 machines being sold to the German military over the next 2 decades.
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  The Poles set up a world leading crypt analysis bureau and hired leading mathematicians such as Marian Rejewski.
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  Marian Rejewski built his own model of the Enigma machine without having actually seen it.
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  a German traitor told Rejewski that the Germans routinely changed the daily key indicator setting for the codes.
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  To find the daily key, Rejewski build 6 replicas of the Enigma machine and connected them.
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  The new machine could run through more than 17,000 indicator settings. He called this machine, ‘the bomb’.
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  The bomb was used to secretly read the traffic from the German Enigma machines for several years.
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  In 1938 Germans added two new roters into the Enigma machine. This made it harder for the Poles to read the traffic
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  The Poles asked their allies, Britian and France to help them with the analysis and codebreaking of the German messages.
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  The British smuggle out the Enigma replica machines two weeks before Germany invaded Poland
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  The smuggled Enigma replicas were taken to the British code . and cypher school at Bletchley Park.
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  Alan Turing, a British mathematician at Bletchley Park thought of a different way of using the ‘bombs’ for testing the German codes.
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  Turing used 180 ‘bombs’ which clicked round letter-by-letter, 20 every second, until they hit the correct one.
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  Hundreds of code breakers at Blechley Park worked round the clock to decipher the German Enigma communications they intercepted
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  Colossus changed the way code breaking was done from electro-mechanical to electronic – it was the first modern day computer
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  In 1943, British engineer, Tommy Flowers, created Colossus
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  Colossus could read paper tape at 5,000 characters a second.
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  The Allied work on codebreaking played a key role in victories such as D-Day. It shortened the length of WW2.