The 12 LED's as seen in the video fade in and out one after the other. The components used in the exercise include an arduino Mega Board, 8 Red LEDs, 8 220 ohm resistors, hook-up wires and the breadboard. The code is from the "built in example arduino" code. The loop works by subtracting a point from the brightness variable causing the dimming in the LED to be at 0. Once this has happened the process from the beginning repeats itself.