Input and output

// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2;     // the number of the pushbutton pin
const int buttonPin2 = 3;     // the number of the pushbutton pin
const int ledPin =  13;      // the number of the LED pin
const int speakerPin = 11; //the number of the speaker pin

// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status
int buttonState2 = 0;         // variable for reading the pushbutton status

void setup() {
  // initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT);
  // initialize the pushbutton pins as inputs:
  pinMode(buttonPin, INPUT);
  pinMode(buttonPin2, INPUT);
  // initialise the speaker pin as output:
  pinMode(speakerPin, OUTPUT);
}

void loop() {
  // read the state of the pushbuttons value:
  buttonState = digitalRead(buttonPin);
  buttonState2 = digitalRead(buttonPin2);

  // check if the first pushbutton is pressed. If it is, the buttonState is HIGH:
  if (buttonState == HIGH) {
    // turn LED on:
    digitalWrite(ledPin, HIGH);
    tone(speakerPin, 440);
  } 
  else if (buttonState2 == HIGH) {
    digitalWrite(ledPin, HIGH);
    tone(speakerPin, 293);
  }
  else {
    // turn LED off:
    digitalWrite(ledPin, LOW);
    noTone(speakerPin);
  }
}