LDR sensor with Arduino

int sensor;

void setup()
{
  Serial.begin(9600);
  pinMode(2,OUTPUT);
}

void loop()
{
  sensor=analogRead(A0);

 Serial.print("SENSOR VALUE=");
 Serial.println(sensor);
 delay(300);

 if(sensor<30)
 {
  digitalWrite(2,HIGH); 
 }
 else
 {
  digitalWrite(2,LOW);
 }
}