A capacitor in electronic circuits serves the primary purpose of storing and releasing electrical energy. This component enables the smoothing of voltage fluctuations and acts as a filter to eliminate noise in circuits. In power applications, capacitors provide stability by maintaining voltage levels. They can also be utilized for timing elements in oscillators and for energy coupling between different stages of circuits. Depending on their type, capacitors can perform various functions, including energy storage, frequency selection, and signal modulation, which are critical for the overall functionality of electronic devices.