What is the meaning and use of the Farad number in Capacitor Bank ?

The Farad size for a capacitor is dependent on the particular use of the capacitor. In some electronic circuits U need a capacitor with more capacitance, in other circuits less capacitance. The capacitance of a capacitor will determine what AC signals that will pass through it easier, when the circuit will become an oscillator, and how much of a charge will be stored up to fire a camera flash.