// Define pin numbers
const int buttonPin = 11; // the number of the pushbutton pin
const int ledPin =  10;  // the number of the LED pin

// Variables will change:
int buttonState = 0; // variable for reading the pushbutton status

void setup() {
  // Initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT);
  // Initialize the pushbutton pin as an input with internal pull-up resistor:
  pinMode(buttonPin, INPUT_PULLUP);
}

void loop() {
  // Read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);

  // Check if the pushbutton is pressed.
  // If it is, the buttonState is LOW:
  if (buttonState == LOW) {
    // Turn LED on:
    digitalWrite(ledPin, HIGH);
  } else {
    // Turn LED off:
    digitalWrite(ledPin, LOW);
  }
}