//set variables for a better overview
      int led = 13;
      int count = 1;

      //here is the setup code it is executed once at the beginning
      void setup() {
        // initialize serial communications at 9600 bps:
        Serial.begin(9600);
        //pin 13 is declared as output
        pinMode(13, OUTPUT);

      }

      //This program part is infinitely fetched again
      void loop() {
        //turn LED on
        digitalWrite(led, HIGH);

        //write text on the serial monitor
        Serial.print("LED on NR:");
        Serial.println(count);

        //wait 1 second
        delay(1000);

        //turn the LED Off
        digitalWrite(led, LOW);
        //write text again
        Serial.println("LED off again");
        //wait 1/2 seccond
        delay(500);
        count++;
      }