The Nano is a small, complete, and breadboard-friendly board based on the ATmega328 (Arduino Nano R3). It has more or less the same functionality of the Arduino Uno but in a different package. It lacks only a DC power jack and works with a Mini-B USB cable instead of a standard one. The Nano is a small, complete, and breadboard-friendly board based on the ATmega328 (Arduino Nano R3). It has more or less the same functionality of the Arduino Uno but in a different package. It lacks only a DC power jack and works with a Mini-B USB cable instead of a standard one.