If you want to add sound to your project, this mini buzzer is a great choice. It is very simple to use, just apply 3V to 5V to it and it will make some noise.

This cylindrical-shaped buzzer has 2 pins that you need to connect to power and ground. Look out for the + sign that indicates the polarity. The diameter is 12mm and it is 9mm tall. It is also PCB and breadboard friendly.