

Ask HN: What has binary to do with computers? - ColinWright

An intelligent, but not very tech savvy, person asked me today: &quot;What has binary to do with computers?&quot;<p>We didn&#x27;t have time for a really long, complete, detailed, start-from-the-ground-up answer.<p>So what would you have said?
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hiddenfeatures
I would have probably said (with some imprecision): Electrical circuits either
carry a current (binary 1) or they don't (binary 0). [Ignoring the fact that
you could also measure the AMOUNT of current carried here] Because of this
underlying limitation in electrics you need to make do with just a binary
system in computers.

Depending on the amount of time remaining I would either go into more depth or
point him towards "Code: The Hidden Language of Computer Hardware and
Software" by Charles Petzold
([http://amzn.com/0735611319](http://amzn.com/0735611319))

~~~
dfritsch
I read that book as a child and loved it, but it is so hard to find a book
named "Code" when that is all you remember. That link just made my day.

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nicholas73
I would explain that it's very difficult to store and measure precise charges,
which is why computers are digital (on or off). Therefore all arithmetic and
logic functions are done in binary numbers, as you can only work with on and
off switches. The underlying hardware itself only allows this, until something
better comes along.

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etep
Because binary allows for _exact_ copies.

Imagine copying a cassette tape or VHS and then copying from the copy.
Eventually you have noise. Same for photocopies, and obviously all of these
are somewhat dated.

This property of noise rejection gives digital computers a significant
advantage over analog computers.

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LarryMade2
Everything - computers are electrical, essentially billions of on-off
switches. On and off is best represented by binary, so at the core of how a
computer works is binary (on-off) math and logic.

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e3pi
ACP, Knuth: SETAN(rus) balanced, unbalanced(balun) ternary, (0,1) arithmetic
encoding, Bechet's weights with Euler's proof... with Nicolai's dual(fewer
Ohaus weights with greater nos comparisons conserved) solution, and remind
savvy person of analog integraph, and instant immediacy of K+E slip stick.

~~~
e3pi
fyi: o(0,1) >> o[0,1]

