Capacitors have several applications in electronic circuits

    Sometimes capacitors are used to store electricity in order to release it at high speeds. This is what the flash uses. Large lasers also use this technique to obtain very bright instantaneous flash effects.

    Capacitors can also eliminate pulsation. If the lines conducting DC voltage contain pulsation or spikes, large capacity capacitors can stabilize the voltage by absorbing peaks and filling in troughs.

    Capacitors can block DC. If a smaller capacitor is connected to the battery, after the capacitor is charged (the capacitor capacity is small, the charging process can be completed in an instant) and there will be no current passing between the two poles of the battery. However, any AC AC signal can flow unimpeded through the capacitor. The reason is that with the fluctuation of AC current, capacitors keep charging and discharging, as if AC current is flowing.

    One of the more important uses of capacitors is to use them with inductors to form oscillators. For more information, see how oscillators work