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Hans Peter Luhn and the Birth of the Hashing Algorithm

The IBM engineer’s hashing algorithm gave computers a way to quickly search documents, DNA, and databases

10 min read
Photo: IBM
Information Scientist: Starting in the 1940s, Luhn devised machines and schemes for parsing information, most notably the now widely used hashing algorithm, which he suggested as a way to sort both numbers and text.
Photo: IBM

In November 1958, at a six-day international conference devoted to scientific information, the inventor Hans Peter Luhn demonstrated a series of his electromechanical machines. They looked rather ordinary. Much like other computing devices of the day, they were boxy and utilitarian, designed to scoop and sort tall stacks of punch cards into slots and bins.

Unlike other computers, however, Luhn’s devices were not designed to work with numbers and calculations but rather with words and sentences. One machine that drew particular attention implemented an algorithm that Luhn called KWIC, for Key Word in Context. Taking in a large number of texts—typically, articles from 500 to 5,000 words in length—the KWIC system could quickly and automatically construct a kind of index.

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Medal of Honor Goes to Microsensor and Systems Pioneer

The UCLA professor developed aerospace and automotive safety systems

3 min read
Photo of a man in a blue jacket in front of a brick wall.
UCLA Samueli School of Engineering

IEEE Life Fellow Asad M. Madni is the recipient of this year’s IEEE Medal of Honor. He is being recognized “for pioneering contributions to the development and commercialization of innovative sensing and systems technologies, and for distinguished research leadership.”

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Video Friday: An Agile Year

Your weekly selection of awesome robot videos

3 min read
Video Friday: An Agile Year

Video Friday is your weekly selection of awesome robotics videos, collected by your friends at IEEE Spectrum robotics. We’ll also be posting a weekly calendar of upcoming robotics events for the next few months; here's what we have so far (send us your events!):

ICRA 2022: 23–27 May 2022, Philadelphia
ERF 2022: 28–30 June 2022, Rotterdam, Germany
CLAWAR 2022: 12–14 September 2022, Açores, Portugal

Let us know if you have suggestions for next week, and enjoy today's videos.

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