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© Mark Dunn - Alamy Stoc
© famouspeople - Alamy
The Automatic Computing Engine (ACE) is the prototype of the first computer built in the UK, developed in 1950 from
Alan Turing computer project.
Alan Turing
(1912-1954)
Information science development
Modern information and computation sciences were born from the invention
of the computability theory by Alan Turing in 1936. In a visionary article,
Turing presents his machines, composed of a tape on which characters
may be written, a read/write head and a mechanism that decides whether
the character that is being read must be replaced by another or the tape
shifted. Turing first showed that these extremely simple machines could perform
any known calculation; he then established two fundamental results, the existence of
universal machines able to compute from a program that is recorded on the tape next to its data, and the
impossibility to compute in finite time whether a given machine will or will not stop on a given data. Thus,
at the very moment he defined the notion of calculability, did he set its limits. The same year, Alonzo
Church introduced the λ-calculus, a logical language still used as the basis for modern programming
languages, and showed it has the same expressive power as Turing machines. He stated the thesis that
any formalism of effective computation to come would also be equivalent to them – a thesis that has never
been contradicted.
But it was not until the end of World War II that the first computers were built, immediately followed
by a surprising and still topical discovery: the difficulty to write and develop programs given the gap