Alan Turing was an English mathematician. During World War 2 he worked on decyphering secret messages and invented a Turing Machine, that became the basis of modern computing.
Turing provided an influential formalisation of the concept of the algorithm and computation with the Turing machine. With the Turing test, he made a significant and characteristically provocative contribution to the debate regarding artificial intelligence: whether it will ever be possible to say that a machine is conscious and can think.
- Turing machine - hypothetical computer used as part of his proof of the "Halting Problem" used in his paper "On Computable Numbers" to show that there are problems that are not solvable by any computer, even one with infinite memory and time.
- Cryptographic work in WW2.
- Early british postwar computer work.
- Being homosexual.
- Losing his British security clearances after WW2 for being homosexual.
- Suicide over loss of clearances and career.