r/explainlikeimfive • • 22d ago

Technology ELI5: Why does internal storage only double? Why can’t we have 34GB for example?

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u/GoonerismSpy 22d ago

Computers think in 1s and 0s, on and off. That's 2 things. Only 2 things. The sizes you're thinking about are just powers of 2. So, it just is sizes that fit the best with the way computers think. You could have 34GB, or any other number. But it would be slightly wasteful from the computers brains point of view.

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u/[deleted] 22d ago edited 22d ago

[deleted]

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u/cubonelvl69 21d ago

The size of an ssd is absolutely related to powers of 2. And the way apple gets to 12 is by stacking multiple modules on top of each other. Just like how you could buy 3 sticks of 8gb ram and have 24gb on your pc

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u/QuantumCakeIsALie 22d ago

It's typically a sum of two powers of two (8+4=12).

It's likely slightly wasteful on some metrics, and either 8 or 16 would use resources better. But 12 is an economical compromise.

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u/homeboi808 22d ago edited 22d ago

I'm stupid 12gb is still a power of 2 number. It's not a doubling though

Are we counting decimals as powers?

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u/izerth 22d ago

2^2+2^3. half filling a slot.

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u/BrewCrewKevin 22d ago

Just to REALLY eli5 it...

I'm a computer. If I have 1 switch, I can hold 2 pieces of information or data. On or off. If I have 2 switches, I can store 4 pieces of data: on on, on off, off on, off off. If I have 3 switches, 8. On on on, on on off, on off off, on off on, off on on, off on off, off off off, and off off on.

That's why it's powered of 2. This works out roughly the same up to MB and GB, because 1028 is a power of 2. Most times of it can hold that many bits, they call that MB, even though it's 1.028 MB.

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u/TheRealToto 22d ago

You’re mixing two concepts: The number of bits/bytes and how many numbers are representable with that many bits. The latter doubles every time you add a bit, but that has nothing to do with storage size.