Light Emitting Diode (LED)

const int LED_PIN = 13;  // Built-in LED or any digital pin
  
  void setup() {
    pinMode(LED_PIN, OUTPUT);  // Set the LED pin as output
  }
  
  void loop() {
    // Basic blinking
    digitalWrite(LED_PIN, HIGH);  // Turn LED on
    delay(1000);                  // Wait for 1 second
    digitalWrite(LED_PIN, LOW);   // Turn LED off
    delay(1000);                  // Wait for 1 second
  
    // Fading example (using PWM)
    for(int brightness = 0; brightness <= 255; brightness++) {
      analogWrite(LED_PIN, brightness);
      delay(10);
    }
    for(int brightness = 255; brightness >= 0; brightness--) {
      analogWrite(LED_PIN, brightness);
      delay(10);
    }
  }