alan turing allen coombs analog computer analytical engine australia bell labs binary numeral system bit bletchley park boolean function brian randell buckinghamshire csirac calculator cheltenham classified information clock signal computer computer program computing cryptanalysis decimal delay line memory dollis hill drum memory edvac eniac eastcote electromechanics electronics encryption film stock george stibitz germany harvard mark i herman goldstine history of computing hardware ieee annals of the history of computing keystream konrad zuse laptop list of fictional computers manchester mark i manchester small-scale experimental machine max newman milton keynes nazi germany newmanry normandy landings paean parallel computing photomultiplier pilot ace plaintext post office research station public record office punched tape shift register supercomputer systolic array teleprinter the national museum of computing thyratron tommy flowers turing completeness vacuum tube vannevar bush williams tube winston churchill world war ii