micro:bit light sensing

A sensor is an example of an input device which detects or measures something and respond to it. So a light sensor responds to the level of light and usually turns a light on or off depending on the light level detected. Streetlights often have light sensors to turn the light on only when it gets dark to save electricity.

While there is no exact light sensor on the BBC micro:bit, you can program the LEDs to detect, measure and respond to the light level in a general way so you can use your micro:bit as a light sensor. You can use this feature in lots of different programs and projects, so you could create a nightlight for a child that senses when it's getting dark and comes on automatically, or a light to attach to a bike or scooter or a bag to help children traveling to school in the dark.