ABC

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(Atanasoff-Berry Computer) The first electronic digital computer. Completed in 1942 by Iowa State Professor John Atanasoff and graduate student Clifford Berry, it employed many of the principles of future computers. For example, although physically in the form of rotating drums, its memory used capacitors that were constantly being recharged like today's dynamic RAM (see DRAM).

The ABC used a standard IBM card reader for input and an odometer-like device for output. For interim storage, Atanasoff devised a binary punch and reader that could very quickly store 1,500 bits on paper sheets by electrostatically burning holes in them. The ABC could solve 29 linear equations with 29 unknowns in one 24-hour day, a marvel for its time.

It Took Years for Recognition

John Mauchly, cobuilder of the ENIAC, began corresponding with Atanasoff in 1940 and visited him in 1941. Although Eckert and Mauchly's machine gained international attention, Atanasoff was not recognized until years later. A 1973 court overturned an ENIAC patent, stating that the basic ideas of the modern computer came from Atanasoff. Some 17 years later at the age of 87, he was finally honored by receiving the National Medal of Technology.

In 1994, an Iowa State University team started building a replica of the ABC. It took three years to complete, but worked exactly as it was supposed to.

Old and New

Clifford Berry (top) stands at the original ABC, circa 1942, while John Erickson, reconstruciton team member (bottom), puts a card into the replica that he helped build more than a half century later. (Images courtesy of Iowa State University.)

ABC Components

This shows all the components of the ABC machine. (Image courtesy of Iowa State University.)

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It's Emmy's Diamond Anniversary

ABC promos say it straight: "If you love TV, this is your night." Tonight, Emmy turns 60 and all five nominees in the category for Outstanding Reality/Competition Host — Tom Bergeron (Dancing with the Stars), Heidi Klum (Project Runway), Howie Mandel (Deal or No Deal), Jeff Probst (Survivor) and Ryan Seacrest (American Idol) — will share hosting duties for the event. The show starts at 8 PM EST, to be broadcast live from LA's Nokia Theater.

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From our Archives: Today's Highlights, September 21, 2008

abbr. for

1. antigen-binding capacity.
2. ATP-binding cassette (see ABC transporter).

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1. aspiration biopsy cytology.
2. airway, breathing, circulation. See cardiopulmonary resuscitation.

  See crossword solutions for the clue ABC.

Dansk (Danish)
n. - abc, alfabetet, abc-bog

Nederlands (Dutch)
abc, alfabet, eerste beginselen, alfabetische gids

Français (French)
n. - alphabet

Deutsch (German)
n. - ABC

Ελληνική (Greek)
n. - αλφάβητο, στοιχειώδεις γνώσεις, αλφαβητικός οδηγός

Italiano (Italian)
abici, alfabeto, abbecedario, ABC

Português (Portuguese)
n. - ABC (m)

Русский (Russian)
алфавит, букварь

Español (Spanish)
n. - abecedario, abecé

Svenska (Swedish)
n. - ABC, alfabet

中文（简体）(Chinese (Simplified))
基础知识, 美国广播公司, 澳大利亚广播公司, 字母, 入门

中文（繁體）(Chinese (Traditional))
n. - 基礎知識, 美國廣播公司, 澳大利亞廣播公司, 字母, 入門

한국어 (Korean)
n. - 초보, ABC순으로 된 여행 안내서

日本語 (Japanese)
n. - エービーシー, 初歩, 入門

العربيه (Arabic)
‏(الاسم) ألحروف الأبجديه, مبدأ علم أو موضوع ما‏

עברית (Hebrew)
n. - ‮האלפבית, עקרונות, יסודות‬

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