Sensors are the eyes and ears of machines,they provide environmental data to machines.A sensor is a device that covert physical parameters into a signal which can be measured electrically.Based on the output the sensors may be classified as Digital and Analog Sensors.

Sensors use as much of microcontroller processing power. consider your micro controllers processing power when deciding what and how many sensor to use.The Arduino is fast enough for our practical purpose.

Sensors used along with Arduino