A tough lesson was that I could even damage components when I wired things the wrong way. The anode positive terminal of an LED is longer than the cathode negative terminal. As a result you should now see your Arduino LED blink with 1000ms intervals. Via an USB blinking light arduino the compiled program could be uploaded to the Arduino. The code starts out with two ardino comment blocks, which are just notes for us humans to read. It is as simple as turning a light on and off.