That property of a system of conductors and dielectric, which permits the storage of electricity when potential difference exists between the conductors. Its value is expressed as the ratio of a quantity of electricity to a potential difference. A capacitance value is always positive. The charge which must be communicated to the body to raise its potential one unit, represented by C= Q/V, where C is the capacitance, Q the quantity of charge, and V the potential.
Capacitance is a measurement of a cable's ability to store an electrical charge, and is expressed in picofarads per foot (pF/ft). Capacitance is especially important in any situation where large amounts of data are being transmitted thru the cable. The higher the capacitance of cable, the more it interferes with high frequency signals.