// Example code when button input uses pull up resistor

// Set the output pin for the LED to pin 13,
// and the input pin for the button to pin 8
int ledPin = 13;
int buttonPin = 8;
// The button can have to states, either it is pressed (LOW)
// or not pressed (HIGH)
int buttonState = 0;

// The setup function runs as soon as the Arduino gets
// connected to power
void setup() {
  // Set the LED pin as output and the button pin as
  // input with a pull-up resistor
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);
}

// The loop is the main loop that runs/loops as fast as
// fast possible executing all code within it
void loop() {
  // Read the button pin using digital read function
  // and store this value in the variable buttonState
  buttonState = digitalRead(buttonPin);
  
  // Use a if statement to check if the button is pressed
  // or not. If the button is pressed the button input pin
  // goes low, if the buttonState variable is low, then turn
  // on the LED pin by setting it high so it becomes bright. 
  // If the button is not pressed, then set the LED pin 
  // to low.
  if (buttonState == LOW) {
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }
}