In electrical engineering, a capacitor is a device that stores electrical energy by accumulating electric charges on two closely spaced surfaces that are insulated from each other. The capacitor was originally known as the condenser, a term still encountered in a few compound names, such as the condenser microphone. It is a passive electronic component with two terminals.
Capacitor
Battery of four Leyden jars in Museum Boerhaave, Leiden, the Netherlands
A simple demonstration capacitor made of two parallel metal plates, using an air gap as the dielectric
A surface-mount capacitor. The plates, not visible, are layered horizontally between ceramic dielectric layers, and connect alternately to either end-cap, which are visible.
A microphone, colloquially called a mic, or mike, is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, and radio and television broadcasting. They are also used in computers and other electronic devices, such as mobile phones, for recording sounds, speech recognition, VoIP, and other purposes, such as ultrasonic sensors or knock sensors.
Shure Brothers microphone, model 55S, multi-impedance "Small Unidyne" dynamic from 1951
David Edward Hughes invented a carbon microphone in the 1870s.
Humphrey Bogart, Jack Brown, and Lauren Bacall with RCA Varacoustic MI-6203 ribbon microphones broadcast to troops overseas during World War II.
Inside the Oktava 319 condenser microphone