There’s not much time left now. If you’re going to put something together to give the youngsters some night terrors in exchange for all that sweet candy, you better do it quick. This la… ...

This instruction is executed only one time. Next is the loop function that sets the pin 13 HIGH (+5V on pin 13), waits a second (1000 ms), then turns OFF the LED (0V on pin 13) and waits another ...