Answer by Joseph Guindi:
He gets more recognition than he deserves in one very important area.
People think that Turing broke the Enigma machine and gave the Allies its most crucial weapon against the Nazis. This is totally and unequivocally false, it was actually broken by Marian Rejewski at the Polish Biuro Szyfrów all the way back in 1932, and him and many of his colleagues barely escaped with their lives through occupied Europe to deliver their secret to their French and British allies as WWII was raging. Some, such as cryptologist Jerzy Różycki were not so lucky and were killed; others like Maksymilian Ciężki were captured and were systematically tortured and deported to concentration camps without ever revealing their secret.
These people didn't just break the Enigma machine before Turing, they actually gave their lives so that Turing and the British government had this information and to keep this information secret. What Turing did was devise the Bombe a more efficient way of cracking Enigma than the previous Polish Bomba device. While no slouch and while he did contribute to the ongoing cracking of Enigma, he had no role in the discovery of the technique, nor did he display (nor did he need to display) any of the heroism that led to this discovery getting to Britain and to protect this secret widely ackowledged to have been crucial to victory over the Nazis.
Esoteric... 