Happy Birthday, Alan
Alan Mathison Turing, OBE, FRS, was born today in Maida Vale, London, in 1912. Every person reading this owes a debt to Turing. As Time put it, naming Turing one of the 100 most influential people of the 20th century: "The fact remains that everyone who taps at a keyboard, opening a spreadsheet or a word-processing program, is working on an incarnation of a Turing machine."
Turing was also an important figure at Bletchley Park, Britain's WWII code-breaking center, and was for a time head of Hut 8, the section responsible for German naval cryptanalysis. He devised a number of techniques for breaking German ciphers, including the method of the bombe, an electromechanical machine that could find settings for the Enigma machine. (If this interests you, check the National Cryptologic Museum's working Enigma the next time you're in the DC area.)
Turing was also gay, living in an era when homosexuality was still both illegal and officially considered a mental illness. After he was outed (in the course of an investigation into his house's being burgled), he was criminally prosecuted - on the same charge as Oscar Wilde had been - and this ended his career, and his life. Offered the choice between prison and probation plus chemical castration, he opted for the latter, but his clearance had been revoked. The next year he died from what was officially declared self-induced cyanide poisoning.
Here's a website maintained by his biographer, Andrew Hodges.