In this chapter, we will explore LEDs with the Arduino. The fastest way to get some feedback from a system or from the Arduino is via an LED. They are simple devices which are either on or off. However, they form the basis for advanced technologies such as LED TVs, projectors, or lasers. In this chapter, we will also see how to use them efficiently and explore some interesting applications for them.

LED stands for Light Emitting Diode and, in its core, it's just a diode that emits light. LEDs are incredibly common these days and can be found at any common electronics shop. Radioshack, Digikey, Farnell, Sparkfun, Adafruit, or Pololu are just a few places we can buy LEDs from, online.