In this chapter, we will cover bend sensors, pressure sensors, light sensors, accelerometer, gyroscopes, and compass sensors. A sensor is a device that can detect events or changes of different kinds and can provide a corresponding output. It is a device that changes some characteristics due to external conditions and can be connected to a circuit, converting the signal so that it can be interpreted by a microprocessor.

With some sensors, you need to build you own circuitry and interpret the data provided by the sensor through code. Some complex sensors have a built-in communication protocol, which enables them to provide data corresponding to their function. The sensitivity of a sensor indicates how much the output data can change.