Part Name: Red, Yellow, Green Diffused LED $5mm$
Part Description: A diode is a fundamental electronic component that is used to control the direction of current in a given part of a circuit. Diodes have two terminals and a specific polarity, so make sure to pay attention to how you connect it in your circuits! The light-emitting diode (or LED, more commonly), however, does more than control current direction; it is capable of creating light! Light will only be created if current flows in the forward direction. LEDs are extremely common in consumer electronic devices. The easiest way to determine LED polarity is by inspecting the terminals. Most manufacturers of LEDs will indicate the anode (positive terminal) with a longer lead while the cathode (negative terminal) will be much shorter. In your kit, you have three different colors: yellow, red, and green. Take a look at the instructional link provided for more info on determining LED polarity.