Single Blinking LED

/*
 * Single Blinking LED program for Arduino UNO
 * Date: 24.11.2018
 * Vidyasagar Academy, Akola
 */

int LED=13; // The variable LED is assigned to pin-13

void setup() // Here we define the output or input pin
{
  pinMode(LED, OUTPUT); // defined pin-13 as output pin
}

void loop() // infinite loop to produce continuous action
{
  digitalWrite(LED, HIGH); // LED will become ON
  delay(1000); // it will remain ON for 1 second
  digitalWrite(LED, LOW); // LED will become OFF
  delay(1000); // it will remain OFF for 1 second
  // after this last line the program will start again
  // and again to repeat the blinking of the LED 
  // up to infinity.
}