Georg Simon Ohm was born in Erlangen, Bavaria (now Germany) in 1789. His father, a selfeducated locksmith, provided Ohm’s early training in mathematics, physics, chemistry and philosophy. In 1805, following a rather spotted and lacklustre formal education, Ohm became a teacher and researcher in mathematics and physics. In 1827, Ohm published his now famous theory of electricity. He theory is now known as Ohm’s Law.

Ohm’s Law outlines the relationship between current, electromotive force and resistance, which is now considered to be the basic law of current flow. Voltage is the electrical force, or "pressure", that pushes electrical current to flow through a circuit. It is measured in VOLTS (V or E). Current is the movement of electrical charge - the flow of electrons through the circuit. Current is measured in AMPERES (AMPS, A or I). Resistance is anything that causes an opposition to the flow of electricity in a circuit. It is used to control the amount of voltage and/or amperage in a circuit. Everything on the circuit, lights, appliances, even the wire itself, causes a resistance. It is measured in OHMS (Ω).

Ohm’s Law states that “The amount of current (amps) flowing in a circuit made up of pure resistances is directly proportional to the electromotive (voltage) forces impressed on the circuit and inversely proportional to the total resistance (Ohms) of the circuit.” In other words, in a complete circuit with constant resistance, a steady increase in voltage produces a constant linear rise in current. By the same token, a steady increase in resistance, in a circuit with constant voltage, produces a progressively (non-linear) weaker current. This can be expressed as a simple formula:

V = I X R