ENIAC facts for kids

Detail of the back of a section of ENIAC, showing vacuum tubes

ENIAC was a huge computer built a long time ago. Its name stood for "Electronic Numerical Integrator And Computer." It was made between 1943 and 1946.

Two clever people, John Mauchly and J. Presper Eckert, designed it. This giant machine used almost 17,500 vacuum tubes. It also had 7,200 diodes and many miles of wire. ENIAC was so big it took up about 167 square meters (1,800 square feet). That's like a very large room!

Many machines are called the "first computer." ENIAC is special because it was easier to program than earlier ones. This made it very powerful for its time.

Because ENIAC used so many vacuum tubes, it often broke down. Finding a broken tube was really hard work. Someone had to find the bad tube, remove it, and put a new one in.

How ENIAC Was Programmed

Making programs for ENIAC was a big challenge. Getting the computer ready for just one program could take days or even weeks!

This was because programming meant moving wires around. For small programs, this wasn't too bad. But for big programs, it was very difficult. This "wiring" method was used until 1948.

After 1948, a special type of memory was added. It was called Read Only Memory (ROM). This meant the computer could read programs from it. Programming then became much faster. People used switches instead of wires. This only took hours, not days.

What ENIAC Was Used For

ENIAC was first designed for the U.S. Army. It was supposed to help calculate firing tables for artillery. These tables told soldiers how to aim their cannons. However, the war ended before ENIAC was finished.

Later, ENIAC was used for other important tasks. When scientists asked if it was possible to make a hydrogen bomb, ENIAC gave the answer in just 20 seconds.

ENIAC also worked out the number pi to 2,000 decimal places. This took it 70 hours!

ENIAC Compared to Modern Computers

Today, a small computer chip (about 2x2 cm) is much faster than ENIAC. Remember, ENIAC filled a whole room! For example, a modern computer can calculate a million decimal places of pi in about ten seconds. That shows how much computers have improved!

The End of ENIAC

ENIAC was turned off for good on October 2, 1955. Today, only about 10 of its original 40 panels still exist. Even though the real ENIAC is gone, you can still run its old programs. This is done using a special program called an emulator on a modern computer.

Images for kids

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  Glenn A. Beck (background) and Betty Snyder (foreground) program ENIAC in BRL building 328. (U.S. Army photo, c. 1947–1955)

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  Programmers Betty Jean Jennings (left) and Fran Bilas (right) operate ENIAC's main control panel at the Moore School of Electrical Engineering. (U.S. Army photo from the archives of the ARL Technical Library)

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  The bottoms of three accumulators at Fort Sill, Oklahoma, US

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  A function table from ENIAC on display at Aberdeen Proving Ground museum.

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  ENIAC on a Chip, University of Pennsylvania (1995) - Computer History Museum

See also

In Spanish: ENIAC para niños