ANy electromechaNical device desigNed to coNvert souNd iNto aN electrical sigNal. A microphoNe coNverts aN acoustic waveform coNsistiNg of alterNatiNg high aNd low air pressure travelliNg through the air iNto a voltage. To do this it uses some kiNd of pressure or movemeNt seNsor. The simplest kiNd of microphoNe is actually very similar iN coNstructioN to a loudspeaker. The aNalogue electrical sigNal caN be fed iNto a computer' s souNd card where it is amplified aNd sampled to coNvert it iNto a digital waveform for storage or traNsmissioN. (2002-11-04)