Objects & Inventions
Computer
The broad class of programmable digital machines that accept data, follow stored instructions (programs), and produce results — from embedded chips to supercomputers.
Photo by Lorenzo Herrera on UnsplashThis entry covers the broad class of programmable digital computers (not only desktop PCs): devices that accept digital input, transform it by executing instructions (programs), and output results.
The history spans mechanical aids (e.g., Babbage’s 19th‑century designs), electromechanical and electronic milestones in the 1930s–1940s (Zuse’s Z3, Colossus, ENIAC), and the postwar adoption of the stored‑program model that underlies modern software and devices. ([plato.stanford.edu](https://plato.stanford.edu/entries/computing-history/))
Quick facts
- A computer is a programmable digital device that accepts data (input), processes it according to stored instructions (a program), and produces results (output); the modern idea follows from the abstract universal/Turing machine and the shift from special-purpose calculators to general-purpose program-controlled machines. ([plato.stanford.edu](https://plato.stanford.edu/entries/computing-history/))
- The ‘stored-program’ model — where a computer holds its program instructions in electronic memory — was first demonstrated by the Manchester Small Scale Experimental Machine (the “Baby”), which ran its first stored program on 21 June 1948. ([manchester.ac.uk](https://www.manchester.ac.uk/about/news/university-celebrates-babys-65th-birthday/))
- Different ‘firsts’ exist depending on the milestone: Konrad Zuse’s Z3 (1941) is widely recognized as the first working programmable electromechanical digital computer, Colossus (delivered to Bletchley Park in 1943/44) was the first large-scale electronic programmable digital machine (designed for cryptanalysis) but did not use internally stored programs, and ENIAC (completed 1945; public 1946) was an early large-scale electronic general-purpose digital computer. ([plato.stanford.edu](https://plato.stanford.edu/entries/computing-history/))
- Early electronic machines were huge and power-hungry: ENIAC used about 18,000 vacuum tubes and consumed on the order of 100+ kilowatts, whereas modern chips are built by packing billions (and in some advanced chips tens or hundreds of billions) of transistors into a single integrated circuit — a difference of many orders of magnitude in size, speed and energy per operation. ([computerhistory.org](https://www.computerhistory.org/revolution/story/78))
- Today ‘computers’ is a broad class that includes embedded controllers, servers, desktop and laptop PCs, smartphones, supercomputers and specialised accelerators — essentially any programmable digital system, not only the familiar desktop tower. ([plato.stanford.edu](https://plato.stanford.edu/entries/computing-history/))
A surprising fact
ENIAC ran on roughly 18,000 vacuum tubes and consumed on the order of 100+ kilowatts of power, yet today a single modern chip can hold billions (and high-end chips hundreds of billions) of transistors — a hardware scale-up of many orders of magnitude. ([computerhistory.org](https://www.computerhistory.org/revolution/story/78))
