What you'll build
Build an LED circuit and program it to blink.
Before you start
You'll learn: digitalWrite() and delay() — turning a pin on and off in time.
You'll finish: An LED circuit that blinks by itself from Arduino pin 9.
Real world: The same trick runs traffic lights, phone notification lights and oven timers.
Then try: Make it blink slowly like a 'tank full' signal, or fast like an alarm.
Who does this: Electrical technician — TVET college diploma, or electrical engineering at university.