Different microphones are used for different applications. As you sit at a table before the screen of the videoconference system, microphone placement varies. Microphones may be installed in the remote control unit of the system, installed in the walls and ceiling, on a table top, or a hand held microphone that may be passed around the room so each participant can be heard. The different technologies are all used to accomplish the same job but with different degrees of success. Five types of microphones are now on the market.
All microphones are transducers, converting one form of energy to another.
Ceramic and crystal microphones. Tiny microphones used in hearing aids. Moving coil microphones 5. Condenser and electret microphones. In videoconference systems, only the electrodynamic and electrostatic microphones are used to detect audio.