In which the reader is asked, quite simply, What is an Algorithm? — and finds the answer rather older, and rather stranger, than expected.
Being an account of cogs and looms and engines of brass; of Signor Pascal's calculating box and Mr. Babbage's unbuilt Engines; of a certain Lady Lovelace who saw further than most; and of sundry other contrivances got up by ingenious persons long before any machine was called a computer.
Wherein two short films are watched, in the company of a partner to be consulted not once but twice; wherein old Euclid's method is recalled, some two thousand years and more since first he wrote it down; and wherein, at the last, the curious Persian origin of a word now spoken a thousand times a day — one al-Khwarizmi's own — is at length discovered.