ENIAC

electronic numeric integrator and calculator

ENIAC is widely credited with being the first true electronic computer, capable of executing an arbitrary program. Earlier computers generally were not electronic, or executed fixed programs. Even so ENIAC lacked some key features of a modern computer. Programming was by setting switches, rather than by storing a program in the memory.

Data was stored in ENIAC using vacuum tubes. Some highlights:

18,000 vacuum tubes
70,000 resistors
10,000 capacitors
6,000 switches
100 foot long, 10 foot high, 3 foot deep (about 30m by 3m by 1m)
140KW power consumption
100kHz clock
5,000 additions per second
500 multiplications per second

Built at Moore School, University of Pennsylvania by JP Eckert and JW Mauchly, work on ENIAC started in 1943 and was completed towards the end of 1945. Considering that the machine was intended to compute ballistic tables for wartime use, its completion was a little late.

But was ENIAC really first? See the Bizarre and British page for an alternative view.

A good source on ENIAC is HH Goldstine. The Computer from Pascal to Von Neumann, Princeton University Press, Princeton, 1972.

Memories are Made of This 17:30 Thurs 12 September 1996
SHB5, Senate House, University of the Witwatersrand, Johannesburg, South Africa