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Why one flipped bit can be found and fixed: Hamming's error-correcting code A single flipped bit can turn a good file into garbage, yet a machine can find and repair it without ever seeing the original. In 1950 Richard Hamming, tired… Computing4 min read23 Oct How to find one name among a billion in 30 looks: binary search Pick a number from 1 to 1,000,000 and you can find it in at most 20 yes-or-no questions. The trick is binary search: look in the middle of a sorted list, throw… Computing4 min read15 Oct Why common letters get short codes in a ZIP file: Huffman coding ASCII spends 8 bits on every letter, whether it is a common e or a rare z. In 1951 a graduate student, David Huffman, found a way to give frequent symbols… Computing4 min read12 Oct How a computer finds one flipped bit and fixes it: Hamming's code A bit can flip in memory, on a disk or in a radio signal, and nothing tells you which one went wrong. In 1950 Richard Hamming published a code that finds the… Computing4 min read9 Oct How honeybees give directions by dancing in the dark A honeybee that finds good flowers can tell her sisters where they are, inside a pitch-black hive, by dancing. She runs in a straight line while shaking her… Biology5 min read2 Oct How a 9th-century scholar cracked secret codes by counting letters For roughly nine centuries after Julius Caesar, swapping each letter for another was a perfectly good way to keep a secret. Then, in 9th-century Baghdad, the… History5 min read30 Sep Hang a chain, flip it upside down, and you have the perfect arch In 1675 Robert Hooke hid a building secret in an anagram. Decoded after his death, it said: as hangs a flexible cable, so, inverted, stand the touching pieces… Engineering5 min read27 Sep Why shared fish, fields and water get used up, and how some places don't When something is shared and nobody controls it, taking a bit more is always worth it for you. You keep the whole gain; the damage is split among everyone… Economics6 min read26 Sep