"Lovelace was deeply intrigued by Babbage’s plans for a tremendously complicated device he called the Analytical Engine, which was to combine the array of adding gears of his earlier Difference Engine with an elaborate punchcard operating system. It was never built, but the design had all the essential elements of a modern computer.
In 1842 Lovelace translated a short article describing the Analytical Engine by the italian mathematician Luigi Menabrea, for publication in England. Babbage asked her to expand the article, “as she understood the machine so well”. The final article is over three times the length of the original and contains several early ‘computer programs,’ as well as strikingly prescient observations on the potential uses of the machine, including the manipulation of symbols and creation of music. Although Babbage and his assistants had sketched out programs for his engine before, Lovelace’s are the most elaborate and complete, and the first to be published; so she is often referred to as “the first computer programmer”. Babbage himself “spoke highly of her mathematical powers, and of her peculiar capability — higher he said than of any one he knew, to prepare the descriptions connected with his calculating machine.”
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