The difference between a diode and a capacitor:

1. Diode is an electronic component with unidirectional conduction current, which is widely applied to switches, rectifiers, voltage stabilizers, etc;

2. Capacitor is used in straightening, coupling, filtering, tuning loop, energy conversion and so on;

3. Varactor Diode is used as an electronic adjustable capacitor;

Besides, Zener Diode can also be used as capacitors, but they are not equivalent.

4. Of course, the appearance of diode and capacitor is definitely different.