ENIAC, the First Computer

ENIAC, the first general-purpose electronic computer, was built at the University of Pennsylvania in Philadelphia between 1943 and 1945 at a cost of $487,000. It weighed 30 tons, occupied a room 1,800 square feet in size, used 18,000 vacuum tubes, and consumed 150 kilowatts of electricity. Its first significant task was calculating ballistic firing tables for artillery. ENIAC could perform 5,000 addition operations per second, which was considered extraordinary speed at the time. A modern smartphone can perform several billion operations per second.

Source: Wikipedia