Read more: Battery Brands Ranked From Worst To Best The Arduino Uno Rev3 is the third revision of the classic Arduino Uno board. Compared to its earlier iterations, it includes upgraded components ...

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.