But all this things are physically wired and connected on Arduino board via USB cabel and my question is if does anybody know if is possible to make it wirelessly using XBee? To be honest, I didn't read much about XBee and I don't know much. Are there any tricks to be carefull? Can it communicate in both ways?
The USB cable is how serial data is transmitted between the PC and the Arduino. The (properly chosen and configured) XBees replace that cable.
What did you mean with "properly chosen and configured"? How could I configure it??
J.C. Woltz Thank you for informations about RF100 or RF200 modules. I was looking on the market if there is anythink else like XBee. Why would you like to recommend the Breakout Board? Is this like a XBee module to put on Arduino Board? And how much it costs? I was looking on product page and I couldn't found any informations about costs.