Alan Mathison Turing, born 1912, died 1954.

See the Alan Turing Home Page, presented by Andrew Hodges, author of 'Alan Turing: the Enigma'

Information on Turing Machines:

• Andrew Hodges' "Computable Numbers, 1936, and the Turing Machine"
• The American Mathematical Society has a page explaining the Turing machine concept.