A sensor is a device that captures physical quantities (variations of light, temperature, sound, etc.) or other changes in their environment. An example of sensor is the Briko which brings us back the measured distance between the sensor and an object. This sensor has a range from 7 to 80 centimeters or 2 to 31 inches; to use the Briko use the function. " read ()" we can read the distance measured by the sensor either in centimeters ( CM ) or inch ( IN ) (if we do not put any arguments to the function, this we return the distance in centimeters). For example, if the sensor detects an object less than 20 centimeters it lights LEDs in red, if it detects an object between 20 and 40 centimeters lights leds in blue and if not detected nothing or detect objects more than 40 centimeters that the LEDs are off: