English mathematician Charles Babbage (1792–1871) is recognized as the first to conceptualize the computer. He worked to develop a mechanical computing machine called the “analytical engine,” which is considered the prototype of the digital computer.

While attending Cambridge University in 1812, Babbage conceived of the idea of a machine that could calculate data faster than could humans—and without human error. These were the early years of the Industrial Revolution, and the world Babbage lived in was growing increasingly complex. Human errors in mathematical tables posed serious problems for many burgeoning industries. After graduating from Cambridge, Babbage returned to the idea of a computational aid. He spent the rest of his life and much of his fortune trying to build such a machine, but he was not to finish. Nevertheless, Babbage’s never-completed “analytical engine” (on which he began work in 1834) was the forerunner of the modern digital computer, a programmable electronic device that stores, retrieves, and processes data. Babbage’s device used punch cards to store data and was intended to print answers.

More than 100 years later, the first fully automatic calculator was invented; development began in 1939 at Harvard University. Under the direction of mathematician Howard Aiken (1900–1973), the first electronic digital computer, called Mark I, was invented in 1944. (The Mark II followed in 1947.) In 1946 scientists at the University of Pennsylvania completed ENIAC (Electronic Numerical Integrator And Calculator), the first all-purpose electronic digital computer. Operating on 18,000 vacuum tubes, ENIAC was large, required great deal of power to run, and generated a lot of heat. The first computer to handle both numeric and alphabetical data with equal facility was the UNIVAC (UNIVersal Automatic Computer), developed between 1946 and 1951, also at the University of Pennsylvania.