ENIAC, often described as the first large‑scale electronic general‑purpose computer, occupied an entire room and marked the start of modern electronic computing, completing development in the mid‑1940s as a landmark engineering project at the University of Pennsylvania and for the U.S. Army.
What was ENIAC
ENIAC (Electronic Numerical Integrator and Computer) was a programmable, electronic, general‑purpose digital computer finished in 1945 that could be reprogrammed to solve a variety of numerical problems and represented a dramatic step beyond electromechanical calculators of the era.
Size and weight
The completed machine weighed more than 27 tonnes and was assembled from multiple large panels and cabinets that together filled a room roughly 10 by 17 metres in footprint, making ENIAC a machine that literally occupied an entire dedicated laboratory space.
Components and power
ENIAC used tens of thousands of vacuum tubes (over 17,000), consumed on the order of 100–200 kilowatts of electrical power and required significant cooling and maintenance, explaining both its large physical footprint and the practical challenges of early electronic computing.
Operation and purpose
Designed originally to compute artillery firing tables for the U.S. Army’s Ballistics Research Laboratory, ENIAC’s architecture supported reprogramming through patch‑cords and switches rather than stored‑program memory, so operating it involved teams of engineers and operators working directly on the hardware.
Legacy
Beyond its immediate military applications, ENIAC proved the practicality of electronic computation and influenced subsequent designs, helping to usher in the rapid development of smaller, more reliable computers and the conceptual foundations of modern computing.