// Define the LED pin
const int ledPin = 5;

void setup() {
  // Initialize the digital pin as an output.
  pinMode(ledPin, OUTPUT); // Sets pin 6 as an output [3].
}

void loop() {
  digitalWrite(ledPin, HIGH); // Turn the LED on (HIGH) [3].
  delay(1000);                // Wait for a second (1000 milliseconds) [6].
  digitalWrite(ledPin, LOW);  // Turn the LED off by making the voltage LOW [3].
  delay(1000);                // Wait for a second [6].
}