/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.

  This example code is in the public domain.
 */

// Pin 13 has an LED connected on most Arduino boards. // give it a name: int led = 13;

// the setup routine runs once when you press reset: void setup() {

  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);     

}

// the loop routine runs over and over again forever: void loop() {

  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second

}