5mm Crystal Green LED Light Emitting Diode

Who doesn't love LEDs? They are bright and blinky, or soft and elegant. They're festive! They're colorful! They're everywhere and they're a lot of fun. We love LEDs when we write tutorials because most electronics hackery is hidden in chips or goes very fast and we can't see or sense it without expensive equipment. But LEDs are easy to see for everyone - this way we can visually identify what is going on inside our microcontroller.

LEDs are so common, that they come in dozens of different shapes and sizes. The LEDs you are most likely to use are the through-hole LEDs with two legs. There are lots of LEDs that are small and hard to solder but these are easy to use with a breadboard because they have long wires we can stick in. The clear or clear-ish bulb is what protects the light emitter (that's where the magic happens). In fact, the first two letters of LED stand for Light Emitting.