#include <Servo.h>
Servo myservo;  // create servo object to control a servo
int potpin = 0;  // analog pin used to connect the potentiometer
​int val;    // variable to read the value from the analog pin


void setup() {
myservo.attach(9);  // attaches the servo on pin 9 to the servo object
}

void loop() {
val = analogRead(potpin);            // reads the value of the potentiometer (value between 0 and 1023)
val = map(val, 0, 1023, 0, 180);     // scale the pot value to use it with the servo (value between 0 and 180)
myservo.write(val);                  // sets the servo position according to the scaled pot value
delay(15);                           // waits to allow time for the servo to move
}