ENIAC, unveiled on 14 February 1946, did about 5,000 additions a second with some 17,468 vacuum tubes. Transistors, integrated circuits, microprocessors, paral…
The US Army paid Mauchly and Eckert about $61,700 to build an electronic calculator for artillery firing tables. It finally cost about $487,000.
About 17,468 vacuum tubes, 27 tonnes and 150 kW in a room of 1,800 sq ft. Six women programmed it with cables and switches.
The transistor did a vacuum tube's switching job in a fraction of the space and power. Its inventors won the 1956 Nobel Prize.
The first program held in a computer's own memory ran in Manchester. New tasks meant loading instructions, not replugging cables.
UNIVAC I was the first US computer built for sale, with about 5,200 tubes. Britain's Ferranti Mark 1 arrived weeks earlier.
Many transistors on one piece of semiconductor. Every later gain in computing depends on this step.
Customers could move to a bigger machine without rewriting software. The mainframe became the backbone of banks and airlines.
A whole processor on a fingernail-size chip, with roughly ENIAC-class power, 25 years after ENIAC.
Vector processing made the Cray-1 the world's fastest computer. About 80 were sold at roughly $8 million each.
After the 1977 Apple II, the IBM PC put computers on office desks worldwide, from $1,565.
By linking thousands of processors. ASCI Red passed a trillion operations a second in 1997, Roadrunner a quadrillion in 2008.
Graphics chips do the same maths on many numbers at once, exactly what neural networks need. Deep learning took off.
Oak Ridge's Frontier became the first public system to pass one quintillion operations a second.
Lawrence Livermore's El Capitan has 11.3 million cores and draws about 29.7 MW. It was No. 1 from late 2024 to 2025.
LineShine in Shenzhen tops the June 2026 TOP500 list, about 440 trillion times ENIAC's additions a second, very roughly.
The biggest machines now hit limits of electricity, cooling and data movement. The race is for more work per watt.
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