Behind every great man, there's a great woman; no other adage more aptly describes the relationship between Charles Babbage, the man credited with thinking up the concept of the programmable computer, and mathematician Ada Lovelace, whose contributions, according to Essinger, proved indispensable to Babbage's invention. The Analytical Engine was a series of cogwheels, gear-shafts, camshafts, and power transmission rods controlled by a punch-card system based on the Jacquard loom. Lovelace, the only legitimate child of English poet Lord Byron, wrote extensive notes about the machine, including an algorithm to compute a long sequence of Bernoulli numbers, which some observers now consider to be the world's first computer program.