More about Voltage / Electricity

The tattoo process requires power. While it is possible to run a
tattoo machine without a proper power supply (as in the actual
power supply device), it is not suggested. You could very easily
hook your tattoo machine up to some type of battery and it
would run. The proper power supply will allow you a level of
control over the primary energy that drives the coils. You can
control voltage with a typical tattoo machine power supply, while
some power supplies let you control more advance features.
In order to understand how the electronic aspect of the machine
operates you must first grasp the basic concepts of electricity.
Electricity can be broken down into three basic sub-components:
voltage, current, and resistance.
An analogy to help illustrate the theory of electricity in a basic
manner would be to think of it as a highway. Voltage would be
the equivalent of the number of cars on the highway, current
would be the rate of speed the cars are going, and resistance
would be the number of lanes on the highway.