Punch cards established a formidable presence but there was still a missing element--these machines, although complex in design, could not be considered computational devices. A formal general-purpose machine that could be versatile enough to solve a diverse set of problems was yet to be invented.

In 1936, after graduating from King’s College, Cambridge, Turing published a seminal paper titled On Computable Numbers, with an Application to the Entscheidungsproblem, where he built on Kurt Gödel's Incompleteness Theorem to formalize the notion of our present-day digital computing.