Power lines are primarily classified by the voltage they carry:

• transmission lines: These are the large, high-voltage lines (typically over 100 kV) supported by tall steel lattice towers or tubular steel poles. They transport bulk electricity over long distances from power plants to substations.

• Distribution Lines: These lines carry lower voltages (from 1 kV to 69 kV) and are typically supported by smaller wooden, concrete, or steel poles. They distribute electricity from substations to local areas, connecting to transformers on poles or on the ground.

• Service Lines: These are the lowest voltage lines that deliver electricity directly from a local distribution transformer to a home or building.