I mean I can run a current through a metal pipe but it doesn’t mean I can store a copy of Skyrim on it.
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Have you ever been shocked by or seen a capacitor discharge spark, after it’s been disconnected from the original power source for a while?
That electrical current was “temporarily” stored in the gap between two electrically conductive plates.
We’ve learnt how to measure whether a capacitor is charged without discharging it, using transistors and ingenious wiring logic.
We’ve also learnt how to make capacitors much, much smaller, so that we can stick a few millions of them inside a computer chip – and since they don’t necessarily discharge when we read them, they store information for a long enough time to be useful for us.
To change the message that they store, we can charge /discharge them at will, which creates a binary code that computers can translate for us.
It is possible to store information in a wire because the speed the wave propagates is finite. It is not how it is done today but [https://en.wikipedia.org/wiki/Delay-line_memory](https://en.wikipedia.org/wiki/Delay-line_memory) was a thing in the 1950- 60s.
The way it is done typically today is with transistors that are electrically controlled switches. The basic idea is you store data by letting electricity through or not. You can think of it as a bunch of light switches that you can flip.
Fast SRAM connects transistors in a loop so store data. A simple layout with transistor and resistors look like https://en.wikipedia.org/wiki/Flip-flop_(electronics)#/media/File:Transistor_Bistable_interactive_animated-en.svg
Regular RAM is DRAM and it stores information by charge in a capacitor or not. You can create charge by rubbing a balloon on your hair. But a bunch of them in a row and rubbing some against your head to change them up bot not others, that pattern of changed vs no changed is data.
Both SRAM and DRAM need power to keep the data. The change in DRAM slowly leaks and you need to refresh it. FLASH memory is built in a special way so the change is stored in a floating gate that it can’t leak away from. The advantage is no power is needed to keep the data there. The disadvantage is storing and reading data is a lot slower than the RAM and there is a limited number of time you can write to it. This is one of the two common ways to store data like games in a computer.
The other common way is hard drives. They store data magnetical by changing the magnetic polarity on part of a disk that rotates. It is like you store data with bar magnets and you change the direction of the north pole to store information.
This all stores data a bit at the time, there are 8 bits in a byte and 1 billion byte in a gigabyte. So there are billions of transistors in the chips we use to store all the data.
Pretty simple. You can use electricity to prevent other electricity from flowing using a few transistors. each one has an power in, power out, and input in. Take 2 of them, hook the power out of one to the input of the other, and the other way around to. then hook power in to a constant voltage.
Now you have a little loop, but electricity can only be flowing in one side of the loop or the other. So that side is “on”, and the other side is “off.” Pick one side to always read the data from, and add 2 more inputs that both bypass the transistors. if you power one line, you set the system into that state, if you power the other, you put it into the other. This circuit is called an Set Reset nor latch (frequently abbreviated RS-Nor latch)
You now have 1 bit of storage. Make 8 of those and you have 1 byte. 1000 of those for a kb, etc.
This isnt how modern data storage works, but this is A way you CAN do. Modern drives do cool tricks to not need constant power, and to be smaller.
You can find some diagrams of this here https://en.wikipedia.org/wiki/Memory_cell_%28computing%29
Another comment already explained it but unpowered memory storage like an SSD is basically millions of little capacitors that store a charge, and whether or not it is charged tells you if there is a zero or a one and that is information. Ssd’s can also fail when the capacitors insulator degrades and the charge leaks out, turning the 1 into a 0 and creating errors.
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