Conductivity is the measure of a solution's ability to pass or carry an electric current. The term Conductivity is derived from Ohm's Law, E=I•R; where Voltage (E) is the product of Current (I) and Resistance (R); Resistance is determined by Voltage/Current. When a voltage is connected across a conductor, a current will flow, which is dependent on the resistance of the conductor.  Conductivity is simply defined as the reciprocal of the Resistance of a solution between two electrodes.