[MUSIC] In this demonstration we're just going to wire a very simple circuit connected to the Arduino. All we're gonna do is the blinking light example, which we've already done. Except we're gonna have the Arduino blink an LED that is not built into the Arduino. So we're just gonna walk through this, just so you get the idea of how you connect something to the Arduino and make it work. And if you look at the Arduino right now. It is now plugged into through USB, so it's getting power. And it's already running the blinking example, so you can see the little LED on there blinking off and on. That's the LED that's connected to pin 13. That's blinking off and on. Just to let you know, that program, that's exactly what's running in the Arduino right now. So, before we wire this together I will disconnect the Arduino from power, that's always safe. Okay, so we'll put that to the side for a second. Now, let's look at the other components we've got. We've got an LED right here. There we go, LED. We've got a resistor, this is 220 ohm resistor. There we are. The two leads resistor. And we got a couple of wires, red one, and black. Right, got some wires. So we're gonna wire this together. What we wanna do is, we wanna connect this LED up to pin 13 of our Arduino. So one side of the LED has to be connected to pin 13, the anode, the positive side. The negative side is gonna be connected through the resistor to the ground. Now why through the resistor? The reason why we have to connect it through the resistor is because if we don't, then our circuit will have very little resistance. Just very low resistance, whatever's in the LED. You'll have so little resistance that will have a lot of current going through. And this LED is rated at 20 milliamps I believe, so if we drive it with more than 20 milliamps we will likely destroy it. So we need to give it some resistance just to reduce the amount of current. 220 ohm resistor right here should be sufficient for that. So, let's wire them together. First, let's put the resistor in, and we can plug it into two arbitrary holes. Okay, so we've plugged it into two holes. Here and here, you can see that. Then I will take the LED. Now the LED, we need to connect it to the resistor, but we need to connect the cathode to the resistor. The anode we wanna connect to pin 13. So the cathode, we look at this, a little hard to see around my hand here. One leg is shorter than the other. So the short leg is the cathode, that's gonna go to negative side, toward the ground. And the long leg, the anode, is the positive side, that's gonna go to the pin 13. So, take and plug in the short legged side into the same row as the resistor. Okay, so, now it is connected. They are on the same row so they are connected. And the long leg side will just shove in to any other row. Force that in here, there we go. Okay, so now we've got the LED connected to the resistor. But this is in no way connected to the Arduino, so now let's go for that. We'll take our black wire and connect that to one side of the resistor. And we're gonna connect that to ground. Now we're gonna get ground from Arduino, so we have several grounds labeled on the Arduino and here goes one right here. So just plug it in, yeah. Yeah, you can see wired into the ground of the Arduino. So one end of the resistor is connected to ground in the Arduino. Now the other wiring we need to do is to take the LED, the anode runner. Plug this red into the same row as the anode. And now connect the anode to pin 13. And what'll happen then, 13, yep, what'll happen then is that when we power this on, the LED on the board will still blink. But this other LED on the red board will also blink, and they'll blink together. Because they're both connected to pin 13. That's what should happen, so let's go and power up. Let's get our USB cable, connect the Arduino, power. And yes, yes indeed, they are blinking together. As you can see, they both blink together and everything worked. Thank you. [MUSIC]