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...