Comparing the Arduino Uno and the Nano, you'll notice that the former includes an onboard DC barrel jack where you can conveniently connect your supply. Because of the Nano's small form factor ...

As with the Uno, you can power the 101 through USB or a DC input jack. A small box holds the Arduino 101 in an anti-static bag and a paper pamphlet. The top of the unit looks very similar to the ...

It has more or less the same functionality of the Arduino Duemilanove, 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.