Abstract

Fifty years ago this month[[June]], in the Computing Machine Laboratory at Manchester University, the world's first electronic stored-program computer performed its first calculation. The tiny program, stored on the face of a cathode ray tube, was just 17 instructions long. Electronic engineers Freddie Williams and Tom Kilburn built the Manchester computer in accordance with fundamental ideas explained to them by Max Newman, professor of mathematics at Manchester. The computer fell sideways out of research that nobody could have guessed would have any practical application. The initial idea germinated thirteen years earlier in the head of Alan Turing, who was working on a recherché problem in mathematical logic. While thinking about this problem Turing dreamed up an abstract machine, nowadays known simply as the 'universal Turing machine' and which, as he put it, would compute 'all numbers which could naturally be regarded as computable'. The machine consisted of a memory in..