Then, chances are you already know what an Arduino ... brain of the board). The Nano features an ATmega328, while the Uno sports an ATmega328P. As they're both 8-bit AVR RISC-based ...

However, while the Uno is a helpful board for your beginner projects, it still has its limitations, so you can't just use it for every one of the Arduino ... it's based on the same microcontroller ...