Capacitors are neither energy nor energy, they are energy storage components.
In the circuit, the capacitor is the same as the resistor. Common capacitors can be divided into: ceramic capacitors, polyester capacitors, electrolytic capacitors, tantalum capacitors, and advanced polyacrylic capacitors, which have different uses. For example, porcelain prices are often used for high frequencies, and electrolysis is used for power supply filtering. 
The above picture shows some examples. Among them, the electrolytic capacitor has positive and negative points, and none of the others. The capacity units of the capacitor are: method (F), micro method (uf), and skin method (pf). Generally we don't use the unit because it is too big. The conversion relationship between units is:
1F=1000000uf 1uf=1000000pf In use, the unit is often seen: nf. 1uf=1000nf 1nf=1000pf
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