Resonance frequency refers to the specific frequency at which a circuit's inductive reactance equals its capacitive reactance, resulting in maximum voltage or current response. At this frequency, the applied voltage and current are in phase, and the circuit behaves as purely resistive. This phenomenon occurs in both series and parallel configurations of coils and capacitors, significantly amplifying signals at the resonant frequency while attenuating others. The concept is crucial for applications like tuning radios and televisions, enabling the selection of a single frequency from a range of signals. Understanding resonance frequency is essential for effectively designing and analyzing electrical circuits.