Electrical devices perform the tasks that they are designed for, thanks to the energy supplied to them by “electricity”. AC generators at a power station provide the electromotive force that causes electrons to oscillate within conductors. The energy of oscillating electrons is transformed into useful work within the electrical device. The human body, inside the skin, can also conduct electricity because its solutions contain many dissolved ions (electrolytes). If due to a fault, electric current flows through the skin into a person from a domestic electrical device, operating on a 50 Hz, 240 V circuit capable of delivering 5A (say); the energy so deposited in the person will cause harm and perhaps death. This is called macro-electrocution as the current required to produce a significant shock is greater than about 5 mA. There are safety precautions in place to prevent this from happening.