Alan Mathison Turing, OBE, FRS (pronounced /ˈtjʊ(ə)rɪŋ/) (23 June 1912 – 7 June 1954) was a British mathematician, logician, cryptanalyst and computer scientist.

Turing is often considered to be the father of modern computer science. He provided an influential formalisation of the concept of the algorithm and computation with the Turing machine. In 1999 Time Magazine named Turing as one of the 100 Most Important People of the 20th Century for his role in the creation of the modern computer, stating: "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."

With the Turing test, meanwhile, 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, the ACE, although it was never actually built in its full form. In 1948, he moved to the University of Manchester to work on the Manchester Mark 1, then emerging as one of the world's earliest true computers.