void setup() {//intialize digital pin 13 as an output. 
pinMode(2, OUTPUT);}
  // the loop funcution run over and over



void loop() {
  digitalWrite(2, HIGH); // turn the LED on (High is the voltage level
  delay(1000); // wait for a second
  digitalWrite(2, LOW); //turn the LED of by making the voltage LOW
  delay(1000); // wait for a second
}