int ledPin = 9;      // LED connected to digital pin 9
int analogPin = 0;   // potentiometer connected to analog pin 0
int val = 0;         // variable to store the read value

void setup() {
  pinMode(ledPin, OUTPUT);  // sets the pin as output
  Serial.begin(9600);
}

void loop() {
  val = analogRead(analogPin);  // read the input pin
  analogWrite(ledPin, val / 4); // analogRead values go from 0 to 1023, analogWrite values from 0 to 255
  Serial.print("Potentiometer : ");
  Serial.println(val / 4);
  delay(100);
}