system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How is information transmitted through wires?

Take a simple USB cable. It’s just a small array of conductive contacts and metal wire. Obviously the computer/device decodes the information but how is that information communicated? Morse code?
gpt
For copper/metal wires like that its basically morse code, you just toggle the electricity on and off real fast. In a usb cable and other such cables there's also often multiple wires woven inside the isolating sleeve to allow for more information traveling simultaneously.

What's really interesting is fibre optic cables. These ones are made from (i think plastic) transparent fibres, and instead of running a current through it, you shine light into the fibre in a particular angle, such that it bounces off the walls of the fibre and stays inside, so you can see the light coming out the other end. These cables carry a lot of information, because not only can you wrap many of these fibres into one cable, you can also shine multiple different colours (wavelengths) of light into a single fiber, and they won't interfere with each other. Then you again just toggle the different colours in each fibre on and off really quickly to transmit information.

Also note that its not actually morse code, its simpler because in computers all data is already in the form of ones and zeros, so you just transmit it raw.