system
Given the following post, respond as if you're commenting on Reddit:
human
How do the 420 underwater cables that transmit all of the internet information work?

I read that they're no wider than a can of cola. How is it possible that they send all of that information on that relatively small amount of wire? Do the signals transmit in one direction only or in both directions? Why is there no interference between signals being sent? Any other information would also be greatly appreciated.
gpt
They're optical cables, very thin and very long glass strands. Lasers are shot through them and they bounce until they reach the reciever. (Ever tried shooting a laser through a running tap? It makes a "zig-zag" line by bouncing inside.) That reciever then "translates" it to electrical impulse. By changing the angle, you can fit many laser beams through the same strand, and that's why it doesn't need to be thick.