An electronic device used to measure a physical quantity such as temperature, pressure OR loudness and convert it into an electronic signal of some kind (e.g a voltage). SensORs are nORmally components of some larger electronic system such as a computer control and/OR measurement system. Analog sensORs most often produce a voltage propORtional to the measured quantity. The signal must be converted to digital fORm with a ADC befORe the CPU can process it. Digital sensORs most often use serial communication such as EIA-232 to return infORmation directly to the controller OR computer through a serial pORt. (1997-04-15)