It’s a significant update. The Arduino UNO and Arduino Mega 2560 update the Duemilanove and Mega respectively. They now use an ATMega8U2 instead of an FTDI USB to serial converter chip.

They're two of the most frequently used Arduino variations, but they serve different purposes. To help you decide which one to get, let's look at the Nano and Uno's primary differences.

There's the 53x101 mm Mega ... Arduino starter kit you bought before, you're already good to go. Most beginner (and even advanced) projects use an Uno, and there really isn't a massive difference ...

The Mega sells for $65, while the Uno goes for $35. Next up? An Arduino board with built-in Ethernet and microSD. Crazy, we know. %Gallery-103287% ...