Equivalent series resistance, also known as ESR, is a very important parameter when selecting a capacitor. ESR includes the resistance of dielectric, plate material, electrolytic solution, and the terminal leads at a particular frequency. ESR acts like a resistor in series with a capacitor. In an electronic circuit, ESR can contribute to power loss, ripple current, and frequency response. Ceramic capacitors have lower ESR, which benefits higher frequency applications, whereas tantalum capacitors have higher ESR, which benefits lower frequency applications such as filtering and bypass functions in a circuit.