What is defined as the ability of a system to store electric charge?

Capacitance is the measure of a system's ability to store electric charge. It fundamentally describes how much electric charge can be stored per unit voltage, which is critical in electrical circuits for applications such as filtering, timing, and energy storage.

Capacitance is associated with capacitors, which are components designed specifically to store energy in the form of an electric field. When a voltage is applied across a capacitor, it accumulates charge on its plates, creating an electric field between them. This stored charge can be released back into the circuit when needed, making capacitors essential in various electronic applications.

In contrast, inductance relates to a system's ability to store energy in a magnetic field when current flows through an inductor, resistance measures how much a material opposes the flow of electric current, and conductance reflects how easily electricity flows through a component. These concepts are distinct from capacitance, which specifically addresses charge storage.