Temperature Sensor is an electric instrument that monitors the temperature of its surroundings and turns the input data into electronic data to record, monitor, or communicate temperature changes. Temperature sensors come in a wide variety of forms. Some temperature sensors need to be in close proximity to the object they are monitoring, whereas other temperature sensors gauge an object's temperature indirectly. Temperature sensors work by transferring electrical signals containing readings. Sensors are made of two metals that produce an electrical voltage or resistance whenever there is a change in temperature by detecting the voltage across the diode terminals. The temperature rises simultaneously with an increase in voltage.