If you were going to kick off a technological revolution, you’d be hard-pressed to do it with more pizazz than Tesla with its electric cars. Flashy, kinda-self-driving, neck-snappingly fast electric cars. But oddly enough, what’s driving it all—the electric motor—is an ancient technology at this point. It’s lost out to the gas engine for over a century, sure, but it’s finally begun to take over transportation, thanks to supporting roles from better batteries and fancy sensors.