void setup() {
  // put your setup code here, to run on
  Serial.begin(9600);
  pinMode(13, OUTPUT); // Set pin 13 as output
}

void loop() {
  // put your main code here, to run repeated
  digitalWrite(13, HIGH); // Turn LED on
  delay(1000);            // Wait 1 second
  digitalWrite(13, LOW);  // Turn LED off
  delay(1000);            // Wait 1 second
  Serial.println("Hello World");
  delay(1000);
}