LED Blink using Arduino

void setup() {
  pinMode(13, OUTPUT);   // Set pin 13 as output (LED pin)
}

void loop() {
  digitalWrite(13, HIGH);  // Turn LED ON
  delay(1000);             // Wait 1 second

  digitalWrite(13, LOW);   // Turn LED OFF
  delay(1000);             // Wait 1 second
}

🔧 Easy understanding:

pinMode(13, OUTPUT) → tells Arduino that pin 13 is for output (LED)
HIGH → LED ON
LOW → LED OFF
delay(1000) → wait for 1 second (1000 milliseconds)

Circuit Text

led long leg = pin 13

led short leg = gnd