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The Surprisingly Long Life of the Punch Card

From 18th-century looms to hanging chads, this technology endured

1 min read
Photo: Randi Klett
Photo: Randi Klett

Paper punch cards, each representing a line of code or data, were how programmers got information into computers from the 1950s on. The concept, though, is a lot older. In 1884 Herman Hollerith borrowed the idea from the Jacquard loom and applied it to his U.S. census machines. Hollerith later founded a company that became IBM, and punch cards became known as IBM cards. Compilers, subroutines, and programs were coded into thick decks of cards, which were then fed through card readers like this ITT Cannon machine, featured in a March 1964 IEEE Spectrum ad. Pity the poor programmer who dropped her deck.

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How Ted Hoff Invented the First Microprocessor

Hoff thought designing 12 custom chips for a calculator was crazy, so he created the Intel 4004

14 min read
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How Ted Hoff Invented the First Microprocessor
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The rays of the rising sun have barely reached the foothills of Silicon Valley, but Marcian E. (Ted) Hoff Jr. is already up to his elbows in electronic parts, digging through stacks of dusty circuit boards. This is the monthly flea market at Foothill College, and he rarely misses it.

Ted Hoff is part of electronics industry legend. While a research manager at Intel Corp., then based in Mountain View, he realized that silicon technology had advanced to the point that, with careful engineering, a complete central processor could fit on a chip. Teaming up with Stanley Mazor and Federico Faggin, he created the first commercial microprocessor, the Intel 4004.

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