The main line typically comes off a pole (but can also be buried underground) to the house where it connects to the meter. Meters are typically installed on the exterior of the home, where they can be read by utility company meter-readers. Most meters are mechanical, with a spinning wheel and mechanical display of numbers. Some newer meters are digital, showing a display on an LCD screen. The meter tallies the amount of electricity used in a home in units of kilowatt hours (kWh). The total increase in the number of kWh from one month to the next is the number used by the electric utility for your bill.