Sure, it isn't such a big deal when you're just starting out as most professionals and experienced users recommend the Arduino Uno. However ... Micro's size and male pin headers make it perfect ...

either have a chip capable of USB or rely on a V-USB implementation, the old fogies of the Arduino world, the Uno and Mega ... between the ‘328 ISP header and the pins on the ’16u2 header.

The aptly named “Nano DIP,” which at 33 mm x 10 mm — about the same size as the ATmega328 on the Arduino Uno — will tickle ... The MCU barely fits between the header pin pads, and the ...

If you're on the hunt for the perfect board, then you've probably come across the Uno and Nano. They're two of the most frequently used Arduino variations, but they serve different purposes.