int LED = 7;    // my LED is pin 7
int BUTTON = 3;  // my button is pin 3

int BUTTON_value = 0; //variable to read the button pin

void setup() {

pinMode (LED, OUTPUT);  // my LED is an output
pinMode (BUTTON, INPUT_PULLUP); // my button is an input (pullup)

}

void loop() {
BUTTON_value = digitalRead(BUTTON); // read the value of the button

if (BUTTON_value == HIGH) { //when the button is not pressed
digitalWrite(LED, LOW);//the LED is off
}
else {
  digitalWrite(LED, HIGH);//the LED is on
}
}