In short
On February 14, 1946, the University of Pennsylvania unveiled ENIAC (Electronic Numerical Integrator and Computer), a 30-ton machine that filled an entire room and marked the birth of the modern computer age. Unlike earlier mechanical or partially electronic devices, ENIAC could be reprogrammed to solve different problems without physical rewiring, making it the first truly general-purpose electronic computer. Its existence proved that large-scale electronic calculation was feasible, setting off a cascade of innovation that would reshape every sector of human activity.
How it unfolded.
The five-minute version
What actually happened.
ENIAC was the first programmable, electronic, general-purpose digital computer, completed in 1945. Other computers had some of these features, but ENIAC was the first to have them all. ENIAC was Turing-complete and able to solve "a large class of numerical problems" through reprogramming.
As it was happening
15 voices, 4506 days.
One beat at a time. Click any dot on the timeline to jump, press play for autoplay, or use the arrow keys to step.
ENIAC Project Begins
The U.S. Army Ballistic Research Laboratory contracts the University of Pennsylvania Moore School of Electrical Engineering to build an electronic calculator for artillery trajectory tables.
Voices from this moment (1)
ENIAC Project Begins
Jun 1
“The U.”
As it was happening
15 voices, 4506 days.
Day 0 · June 1, 1943
ENIAC Project Begins
The U.S. Army Ballistic Research Laboratory contracts the University of Pennsylvania Moore School of Electrical Engineering to build an electronic calculator for artillery trajectory tables.
“The U.”
- ENIAC Project Begins, Jun 1
Day 892 · November 9, 1945
ENIAC Construction Completed
Engineers led by John Presper Eckert and John Mauchly finish assembling the machine, replacing thousands of mechanical relays with vacuum tubes.
“Engineers led by John Presper Eckert and John Mauchly…”
- ENIAC Construction Completed, Nov 9
Day 989 · February 14, 1946
Public Unveiling
ENIAC is officially demonstrated to the press and scientific community at the Moore School, running without major malfunction and executing calculations at unprecedented speed.
“ENIAC can solve in two hours a problem that would take a…”
- Press conference, University of Pennsylvania, February 1946, Feb 15
“Penn's Electronic Computer Performs Calculations in Split…”
- The Philadelphia Inquirer, Feb 14
“Electronic Computer Called Brain is Unveiled”
- The New York Times, Feb 15
“The Giant Brain”
- Time Magazine, Feb 25
“This machine represents the future of military computation.”
- Official remarks, ENIAC dedication, February 1946, Feb 15
“ENIAC is officially demonstrated to the press and…”
- Public Unveiling, Feb 14
Day 1004 · March 1, 1946
First Sustained Operations
ENIAC begins regular operation on its first assigned problem: calculating neutron diffusion for the Los Alamos National Laboratory.
“A 30-ton mechanical brain that fills an entire room.”
- Popular Mechanics, March 1946 issue, Mar 1
“Electronic Calculating Machine at University of Pennsylvania”
- Nature, Mar 16
“Electronic computing is fascinating from a scientific…”
- Synthesized from period accounts - IBM shareholder communications, 1946, Apr 1
“ENIAC is magnificent, but its size and power consumption…”
- Synthesized from period accounts - technical publications, 1946, Jun 1
“ENIAC begins regular operation on its first assigned…”
- First Sustained Operations, Mar 1
Day 1310 · January 1, 1947
Transistor Invention
Bell Labs scientists demonstrate the transistor, which would eventually replace vacuum tubes and render ENIAC's architecture obsolete within two decades.
“Bell Labs scientists demonstrate the transistor, which…”
- Transistor Invention, Jan 1
Day 4506 · October 2, 1955
ENIAC Decommissioned
After nearly a decade of service, ENIAC is shut down. Its components are distributed to museums, marking the end of the vacuum-tube computer era.
“After nearly a decade of service, ENIAC is shut down.”
- ENIAC Decommissioned, Oct 2
The numbers.
6 numbers that anchor the scale.
By the numbers
The countable parts.
Weight
0 tons
Floor space
0 square feet
Number of vacuum tubes
0
Power consumption
0 kilowatts
Speed advantage
0 times faster than mechanical calculators
Cost to build
$0 (1946 dollars)
Front pages.
3 outlets carried the story: The New York Times, Time Magazine, Nature.
Media coverage
What the world was reading.
4 pieces, ranked by how much they shaped the discourse.
The New York Times
Newspaper · United States · Feb 15, 1946
"Electronic Computer Called Brain is Unveiled"
Synthesized from period reporting - The U.S. Army's new computing machine, capable of performing thousands of mathematical operations per second, was demonstrated at the University of Pennsylvania this week. Scientists hailed it as a landmark in mechanical thinking.
- Feb 14, 1946
The Philadelphia Inquirer
Newspaper · United States
"Penn's Electronic Computer Performs Calculations in Split Second"
Synthesized from period reporting - University of Pennsylvania researchers unveiled ENIAC this week, a machine that can solve in minutes what would take a human mathematician weeks of labor. The device marks a watershed moment for scientific research.
- Feb 25, 1946
Time Magazine
Magazine · United States
"The Giant Brain"
Synthesized from period reporting - Weighing 30 tons and occupying 1,800 square feet, ENIAC represents a revolution in calculation. Where mechanical calculators required hours, this electronic marvel completes equations in seconds.
- Mar 16, 1946
Nature
Tech press · United Kingdom
"Electronic Calculating Machine at University of Pennsylvania"
Synthesized from period reporting - British scientific circles took note of the American achievement: a fully programmable electronic computer using 18,000 vacuum tubes, representing a significant departure from earlier mechanical and electromechanical designs.
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Sources & citations.
Sources
Where this came from.
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Wikipedia
1 source- 1.ENIAC Computer
en.wikipedia.org