Voltage (or electrical potential energy) is the strength of an electric current.
Whereas the power of a corded jigsaw is determined by the wattage of the machine, the power of a cordless model is indicated by its voltage.
Corded jigsaws
However, when thinking about main-operated jigsaws, voltage is still important.
Corded jigsaws are available with a voltage of either 110 volts or 240 volts, however this difference in voltage does not result in a difference of power.
Instead, the voltage of a corded jigsaw specifies whether the tool can be plugged straight into the mains electricity supply or whether it will require a step-down transformer in order to run safely.