Here is the back panel of the rebuilt bombe machine at Bletchley. At the launch of the exhibition, Bletchley Park codebreaker Captain Jerry Roberts, now aged 91, who worked on cracking the Tunny cipher used by Hitler's high command, paid tribute to Turing's contribution in helping decipher Nazi messages.
"In the spring of 1941, Britain was losing the war. The German wolf packs were sinking the ships bringing in food and raw materials to Britain left, right and centre - and of course we didn't know where they were out there, waiting, lurking," he said.
"At that juncture, Turing made his fantastic achievement of breaking naval Enigma. At that juncture, there was no other salvation for Britain. Once naval Enigma was broken, the sinkings dropped by 75 per cent."
But despite his achievements at Bletchley, Turing remained a reserved figure, Roberts recalls.
"We never worked together but I used to see him walking the corridors with his gaze averted because he was a very shy man," he said.
"He was an amazing hero, but he didn't project himself in that way - the opposite in fact."
Photo: Nick Heath/TechRepublic
Nick Heath is chief reporter for TechRepublic. He writes about the technology that IT decision makers need to know about, and the latest happenings in the European tech scene.