Ada Lovelace met Charles Babbage as an eighteen-year-old at a party thrown to show to the best of London society Babbage’s Difference Engine. The Engine was fantastic new device that — using the latest Industrial Revolution skills of precision machine tooling — for the first time allowed for automation in the performance of complex calculations.
Babbage was designing the next version of his calculating machine, The Analytical Engine, and asked Lovelace to translate a description he had received from Italian mathematician Luigi Menabrea discussing the principles behind it. The original work was a little over eight thousand words; Lovelace appended her own notes, extending the translation to over twenty thousand words. In the process she described a method for calculating Bernoulli numbers, creating what is now recognized as the first algorithm intended to be processed by a machine.
The Analytical Engine took its lead from the Jacquard Loom by performing its tasks according a series of punch cards, which would be widely used to program computers well into the 20th Century. As planned, it:
incorporated an arithmetic logic unit, control flow in the form of conditional branching and loops, and integrated memory, making it the first design for a general-purpose computer that could be described in modern terms as Turing-complete.
Unfortunately, the Analytical Engine was never built in Babbage’s or Lovelace’s lifetimes. Ada died when she was thirty-six, probably the victim of misguided blood-letting by 19th century doctors. Babbage worked on various designs until his death in 1871, but an actual working specimen engine was not completed until 1991 when the UK’s Science Museum built a version (weighing 2.6 tonnes and consisting of 4,000 separate parts) using materials only available to Babbage himself.
Ada is certainly not forgotten though. She is immortalized in the name of the Ada programming language, and each year October 15 is recognized as Ada Lovelace Day, “an international celebration of the achievements of women in science, technology, engineering and maths.”