What is the difference between 120v and 220v?

To achieve 900 watt of power, 4.1 Amps would be required with 220v wiring, whereas it takes less current with the same wire.By comparing 110 volts and 220 volts, we know that both do the same thing, but the difference is that when 220 volts wiring is used, it takes less power than with 110 volts.and so, to reach 900 watts of power, 4.1 amps would be needed with 220v wiring, while about 8.2 amps would be needed with.