Image courtesy of SparkFun Electronics

You’ll use this small (half-size) breadboard in all your projects to add additional circuitry to your Arduino. The breadboard has two power rails on each side for both power and ground connections. The break in the middle makes it easy to mount integrated circuits to the breadboard. If you find yourself running out of space, you can upgrade to a full-size breadboard.

Buy a half-size breadboard from Amazon, SparkFun, Adafruit, or Newark.