int potPin = A0; // Analog input pin connected to the potentiometer
int potValue = 0; // Value that will be read from the potentiometer
int led = 9; // Pin 9 (connected to the LED) is capable of PWM
// Runs once at beginning of the program
void setup() {
 pinMode(led, OUTPUT); // Set pin 9 to output
}
// Loops continuously
void loop() {
 potValue = analogRead(potPin); // Read potentiometer value 
 // from A0 pin
 analogWrite(led, potValue/4); // Send potentiometer value to LED
 // to control brightness with PWM
 delay(10); // Wait for 10 ms 
}