<human>:  What is the function of a capacitor?
<bot>: A capacitor is an electronic component that stores electrical energy in an electric field. It is commonly used to maintain a steady current or voltage level in a circuit by acting as a buffer. It can also be used to filter out unwanted frequencies in a signal, block direct current in alternating current circuits, and regulates power supply voltages. It is also used for several other purposes like timing circuits, tuning circuits, signal coupling, signal processing and more.