World's First Computer Programmer
First things first — Ada Lovelace was a champion for Charles Babbage's calculating machine, the Analytical Engine, when no one else was. She is celebrated for having the foresight that an instrument of this kind had endless practical and scientific uses. Looking at how much technology is integrated into our lives today, we'd say she was absolutely right.
Ada drafted a plan of how the Analytical Engine might calculate Bernoulli numbers, a plan that is now considered the first "computer program."