Location sound supervisor - The individual on set ultimately responsible for the correct recording and mixing of all sound sources on the film or TV location or studio.

He or she is in charge of all aspects of sound and often works with a Boom Operator

field or location Mixer - A mixer that is used on site at the location of a film, tv or radio production that allows the location sound supervisor to both connect together and then mix the sound sources from different sources on a film or TV location, including presenters, actors and location sound sources.

The mixer is usually much smaller than mixers used in recording studios and will either be a table top mixer with 8-12 channel inputs (often mounted on a rack of sound equipment) or worn over the shoulder by the location sound supervisor.

Shoulder worn location mixers usually have fewer inputs - between 2 to 6 inputs)

In both cases the OUTPUT of the mixer - which can be 2,3,4 or more sound signals) is sent EITHER back into the main camera (which can often record 2,4 or 8 tracks of audio at the same time) or a portable sound recording device.

a lapel microphone or lavalier (or lav mic) is a small electret or dynamic microphone used for television, theatre, film and public speaking applications, in order to allow hands-free operation.

They are most commonly provided with small clips for attaching to collars, ties, or other clothing. The cord may be hidden by clothes and either run to a radio frequency transmitter in a pocket or clipped to a belt (for mobile work), or directly to the mixer (for stationary applications).

A lapel microphone or lavalier (or lav mic) is a small electret or dynamic microphone used for television, theatre, film and public speaking applications, in order to allow hands-free operation.

They are most commonly provided with small clips for attaching to collars, ties, or other clothing. The cord may be hidden by clothes and either run to a radio frequency transmitter in a pocket or clipped to a belt (for mobile work), or directly to the mixer (for stationary applications).

a boom mic is a type of microphone which is mounted (usually with shock absorbing springs or chords to avoid noises) at the end of a "Boom pole" or "fishing pole" which itself is a long extendable/telescopic pole that allows the Boom Operator to reach OVER a presenter or actor and lower the microphone as close in to a presenter or actors direction of speech but WITHOUT the boom pole or rod (or MIC) appearing in the frame.

The microphone used at the end of the boom pole is USUALLY a "shot-gun" or "directional" microphone which is therefore often called a BOOM Mic