Why do all modern-day computers use binary then?
Simple answer: Computers weren’t initially designed to use binary… rather, binary was determined to be the most practical system to use with the computers we did design. Full answer: We only use binary because we currently do not have the technology to create “switches” that can reliably hold more than two possible states. (Quantum computers aren’t exactly on sale at the moment.) The binary system was chosen only because it is quite easy to distinguish the presence of an electric current from an absense of electric current, especially when working with trillions of such connections. And using any other number base in this system ridiculous, because the system would need to constantly convert between them. That’s all there is to it.
