Alan Mathison Turing, OBE, FRS was an English mathematician, logician and cryptographer.
Turing is often considered to be the father of modern computer science. 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. He later worked at the National Physical Laboratory, creating one of the first designs for a stored-program computer, although it was never actually built. In 1948 he moved to the University of Manchester to work on the Manchester Mark I, then emerging as one of the world's earliest true computers.