A mining engineer from Buffalo, New York, Hollerith didn’t set out to be an inventor. But the challenge of stripping banal labor from the census process appealed to him. After a colleague at the Census Office proposed the idea of automating calculations in 1879, he got to work designing the new apparatus.

Hollerith applied for his first patent in 1884, outlining a proposed method to store data using holes punched into strips of paper, similar to how player pianos read thick rolls of paper full of notched notes. By 1886, he switched to punched cards, and a year later he applied for a second patent. The patents were granted in 1889.

Punched cards weren’t Hollerith’s idea. About 80 years prior, Joseph Marie Jacquard of France devised a way to use punched cards to automate steam-powered weaving looms. In the mid-1830s, English mathematician Charles Babbage developed plans for a computing engine — later dubbed the Analytical Engine — that could do math using instructions from punched cards. But Hollerith was the first to apply the principle to data processing.

In 1886, Hollerith began testing his machine by compiling mortality statistics for Baltimore, Jersey City and New York City. In 1888, the Census Office held a competition to find the fastest tabulating solution. The winner would earn a contract to process the 1890 census. His two competitors clocked in at 144.5 and 100.5 hours to capture the data used for the challenge. Hollerith came in at 72.5 hours. Hollerith’s machine also excelled at the task of preparing the data for tabulation, logging a time of 5.5 hours, which dramatically outperformed his competitors’ times of 44.5 and 55.5 hours.