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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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Poll: Would You Want to Work a Shorter Week?

Weigh in with your thoughts on a four-day workweek

2 min read
Person holding a giant sized pencil standing next to a giant sized calendar with days crossed out to show a four-day workweek.
iStock

When I worked for a company in Texas a few years ago, one of the benefits I enjoyed was a four-and-a-half-day workweek. The system enabled my colleagues and me to run some personal errands, see our doctors, and pick up our kids from school, among other activities.

The COVID-19 pandemic required many companies to adopt a flexible work schedule to keep their operations open. Many allowed their employees to work from home full time. Nowadays plenty of those employers are trying to persuade their workers to return to the office full time, but they are facing some resistance.

One solution some companies are trying is a four-day, 32-hour workweek for the same pay.

​Does your company offer a four-day workweek?

Would you like to work a four-day workweek?

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Xiaomi’s Humanoid Drummer Beats Expectations

Solving drum-playing helped quest for whole-body control

3 min read
A black and white humanoid robot sits at an electronic drum kit

When Xiaomi announced its CyberOne humanoid robot a couple of months back, it wasn’t entirely clear what the company was actually going to do with the robot. Our guess was that rather than pretending that CyberOne was going to have some sort of practical purpose, Xiaomi would use it as a way of exploring possibilities with technology that may have useful applications elsewhere, but there were no explicit suggestions that there would be any actual research to come out of it. In a nice surprise, Xiaomi roboticists have taught the robot to do something that is, if not exactly useful, at least loud: to play the drums.

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