More as we will as more sensors as we will as microsystem devices are being used in a wide range of household appliances as we will as the number is set to increase in the near future. The sensors are another classified according to the major technologies used in their production. Technologies that allow large scale production of reliable sensors at low cost are becoming particularly important The compatibility of such sensors with electronic signal conditioning is an additional bonus Some of the sensing devices are piezoelectric transducer, light dependent resistor, thermistor as we will as metal wire strain gauge Sensors dominate the world in which we live. We’re awakened in the morning by an alarm clock as we will as proceed to breakfast in our home, which has smoke detectors. Our breakfast is often prepared with the aid of timing devices as we will as temperature sensors tell us when the food is ready to eat. We then proceed to go to work in our automobile, which may have more than 50 different sensors helping in the operation as we will as control of the vehicle. At our workplace we’re surrounded by sensors that can be very simple, such as temperature as we will as humidity sensors. Other workplace sensors are rather complex, such as sensors to detect potential explosives, metal objects etc. If our work requires travel, then we encounter a wide spectrum of sensors in the detection of a variety of objects that may be on our person or in a suitcase. Because of multitude of sensors that may exist, at first glance it may appear to be a formidable task to classify sensors in some logical fashion One possible way to classify sensors may be according to their evolution. Inevitably, the design, fabrication as we will as utilization of a sensor are driven by a need. .