What Is a Mic and How Is It Used When Capturing Digital Video?

A Mic, or Microphone is a device designed to capture and convert sound into a digital signal so that it can be recorded to a storage medium. A digital camera which is able to record audio must have  built-in mic in order to do so, built-in mics are generally low quality but allow the simultaneous recording of audio and video without the need for external equipment. Many higher end cameras now have a dedicated mic input port which allows the for use of higher quality, external audio capturing equipment.

An external microphone.