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ENIAC, finished in 1945 at the University of Pennsylvania, was the first programmable, general-purpose electronic computer. It filled a large room and weighed about 27 tonnes, and each new problem had to be set up by rewiring cables and turning switches, a job that could take weeks.

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John Mauchly and J. Presper Eckert designed ENIAC for the US Army, to calculate the firing tables gunners used to aim artillery. Until then such tables were worked out by hand by 'human computers', many of them women. ENIAC's 18,000 or so vacuum tubes, glass valves that switch electric current on and off, let it make about 5,000 additions a second, roughly a thousand times faster than earlier electromechanical machines. It was unveiled in February 1946, and the press called it a 'giant brain'. Six women worked out how to program it: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas and Ruth Lichterman. Their role was overlooked for decades; in 1997 they were inducted into the Women in Technology International Hall of Fame. ENIAC stayed in use until 1955.

Türkçe oku
1945'te Pennsylvania Üniversitesi'nde tamamlanan ENIAC, programlanabilen ilk genel amaçlı elektronik bilgisayardı. Koca bir odayı dolduruyordu ve yaklaşık 27 ton ağırlığındaydı. Her yeni problem için kabloların yeniden bağlanması ve anahtarların tek tek ayarlanması gerekiyordu; bu hazırlık haftalar sürebiliyordu.

ENIAC'ı John Mauchly ile J. Presper Eckert, ABD Ordusu için tasarladı. Amaç, topçuların nişan alırken kullandığı atış tablolarını hesaplamaktı. O güne kadar bu tabloları, çoğu kadın olan “insan bilgisayarlar” elle hesaplıyordu. ENIAC'ta, elektrik akımını açıp kapayan cam vakum tüplerinden 18.000 kadar vardı. Bu tüpler sayesinde saniyede yaklaşık 5.000 toplama yapabiliyor, önceki elektromekanik makinelerden bin kat kadar hızlı çalışıyordu. ENIAC Şubat 1946'da kamuoyuna tanıtıldı ve basın ona “dev beyin” adını taktı. Nasıl programlanacağını ise altı kadın çözdü: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas ve Ruth Lichterman. Emekleri onlarca yıl görmezden gelindi; 1997'de Women in Technology International'ın Onur Listesi'ne alındılar. ENIAC 1955'e kadar kullanıldı.

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