Time Constant: Denoted as $\tau = RC$, it represents the time required for the capacitor's voltage to reach approximately 63% of its final value during charging or discharging.
Kirchhoff's Voltage Law (KVL): $\Sigma V = 0$ around any closed loop in a circuit; used to formulate differential equations in electrical circuits.
Natural Response: Describes how voltages and currents decay over time when no external energy sources are present.