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Ed S
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Excellent short story - funny, and full of relevance.

(via a comment on a discussion about The Future of Go Summit, where Google's AI is showing off against the best human players.

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From 1953, a remarkably simple and subtle analogue computer - trace the outline of a shape, and read off the area of the shape. Think about how you might do that... I don't think I'd ever be able to do it so simply! "Planimeters are mechanical instruments which can measure the area of closed regions in the plane. Planimeters are used in medicine for example to measure the size of the cross-sections of tumors or organs, in biology to measure the area of leaves or wing sizes of insects, in agriculture to measure the area of forests, in engineering it is used to measure the size of profiles."

Here's the one simple trick: "The measurement is based directly on Green's theorem in multi-variable calculus: the planimeter integrates a line integral of a vector field which has constant curl."

So, if your name is Green, you have a chance.

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Several arithmometers and slide rules, and many more beautiful things from radios to space probes and calculators to Mars bases, on this site from the Russian Polytechnic Museum:
(And many other things too, if you care to search: a Swyft prototype for example)
"This folding arithmometer developed by Ivan Fedorovich Kucherov performs all arithmetic operations. For addition and subtraction a fixed part of the device is used, which is a modification of Kummer's adding machine, whereas for multiplication and division involves the moving calculation tables."
See also

via +Kam-Yung Soh

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A good slice of computer history (in German.) You will visit several computer museums (Heinz Nixdorf, Bletchley Park), will meet Babbage, Turing, Zuse, and see interviews with Zuse Jr. and George Dyson.
Second part is here:

In German: nice documentary on computing history. Even if you don't understand German, some very interesting images of Konrad Zuse at work and its creations, relay computers, etc.

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Tape loops, synthesisers, the BBC Radiophonic Workshop: Delia Derbyshire! (Who? Yes, Who - the Doctor Who theme, most famously. "One of the earliest and most influential electronic sound synthesists. She was musically active from 1962 until the mid seventies.")

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This jigsaw puzzle has three solutions - be amazed! One solution has a missing piece and another has an extra piece.
Via Interesting Esoterica at
(on a decentralised social network with a maths and CS emphasis)
/cc +Alex Fink

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A DIY paper computer, from 1958... just add scissors and pins and an hour of your time. But don't get over-excited, this is just 1 bit computing, unlike the much more sophisticated 3 bit Digi-Comp I from 1963. What does a 1 bit computer do? Depends on the instruction length, of course, but in this case it's a zero bit instruction - it can only do one thing, which is to accumulate from one storage register to the next. I'm not entirely sure, but I think that means it can toggle one of two bits. Nonetheless "the computer expert will recognise that [this machine] contains most of the units of a large-scale computer, but in simplified form."
(This post unrelated to the much more modern and open-ended 1-bit project from +Dave's Dev Lab as seen at
- video within!)
Also ref:

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This series of short videos packs in quite a bit of information - but it's not so much Computer Science itself, more an orientation covering various CS topics.

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Open source down to the bare metal - there's a 320MHz RISC-V CPU in this Arduino-type board, for just $59. (And the I/Os are 5V tolerant too.) Performance of 1.61 DMIPs/MHz and power efficiency of 3.16 DMIPS/mW. And a massive 16k of SRAM - so no need to ask if you can run Linux on this. Run in your browser instead!

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Satellite lost, because the Moon was there. (2004) Boeing designed a launch trajectory which neglected the effect of lunar gravity. "Superbird 6 was delivered by its launch vehicle to its predefined supersyncronous transfer orbit, but in defining this orbit the gravitational influence of the moon had been forgotten. The satellite was rescued but at a cost of most of its fuel.
Additionally, the outer parts of the solar panels had reduced power, possibly due to overheating during the low perigee pass (most satellites deploy in their correct orbit with solar panels fully extended). Thus a simple computer glitch (forgetting about the moon) caused a major loss."
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