Very good book for those who want to get Arduino

The problem of the Arduino is that this is techno exceeded my senses. I went to the Raspberry Pi that seems to offer much more functionality. The Arduino is still good to make small servo simple enough even if we proudly present ds robot controls.
I bought it to convince me that it was better to focus myself on the Raspberry Pi ,, although the examples he cites are in my view be transposed without too much difficulty provided to remember that the raspberry operates at 3.3 v and the Arduino 5v