What is computer data? when we say it is "1" or "0", it means that voltage is high or low.?

if data is flowing in a network wire or any other medium in form of 1s and 0s, does it mean that voltage is in discrete form in the medium.(i mean that in wire voltage is like "high voltage, low voltage, high voltage, high voltage, low voltage low voltage, low voltage, high voltage". data (10110001))