A capacitor is a component that stores electricity and potential energy. Two conductors that are close to each other, with a layer of non-conductive insulating medium sandwiched between them, form a capacitor. When a voltage is applied between the two plates of a capacitor, charges are stored. Capacitors play an important role in circuits such as tuning, bypass, coupling, and filtering. Capacitors are mainly classified as follows: 1. Structure: fixed capacitors, variable capacitors, and fine-tuning capacitors; 2. Electrolytes: organic dielectric capacitors, inorganic dielectric capacitors, electrolytic capacitors, electric heating capacitors, and air dielectric capacitors, etc; 3. Usage: high-frequency bypass, low-frequency bypass, filtering, tuning, high-frequency coupling, low-frequency coupling, small capacitors, etc; 4. Manufacturing materials: ceramic capacitors, polyester capacitors, electrolytic capacitors, tantalum capacitors, as well as advanced polypropylene capacitors, etc; 5. High frequency bypass: ceramic capacitors, mica capacitors, glass film capacitors, polyester capacitors, glass glazed capacitors, etc; 6. Low frequency bypass: paper capacitors, ceramic capacitors, aluminum electrolytic capacitors, polyester capacitors, etc; 7. Filtering: aluminum electrolytic capacitors, paper capacitors, composite paper capacitors, liquid tantalum capacitors, etc; 8. Tune: ceramic capacitors, mica capacitors, glass film capacitors, polystyrene capacitors, etc; 9. Low coupling: paper capacitors, ceramic capacitors, aluminum electrolytic capacitors, polyester capacitors, solid tantalum capacitors, etc