Charles Babbage designed the first mechanical computer in the 1820s, the Difference Engine, a machine never fully built in his lifetime but a direct ancestor of everything that followed. The film traces the line from Babbage through the punch-card tabulators built for the 1890 US census, work that gave rise to the company that became IBM in 1911, initially a maker of time clocks and tabulating equipment. World War II accelerates the story: the demand for missile trajectory calculations and codebreaking pushes engineers toward the first electronic computers, and vacuum tubes give way to transistors, shrinking machines that once filled rooms into something that could eventually sit on a desk. The narrative closes with Steve Jobs and Bill Gates, contrasting Apple's focus on design against Microsoft's focus on accessibility and function, and the competition between their companies that shaped the personal computer market. The film moves chronologically through invention, wartime necessity, and corporate rivalry to show how computing became a household fixture.