There are many models of Arduino boards from what I've read. (http://arduino.cc/it/main/boards) and (http://en.wikipedia.org/wiki/Arduino) Speed, memory, and I/O vary in most. But I have found nothing that says what model is old and obsolete and what model is more recent, or what model is most useful for a given application. Is that information around?
I have no experience with Arduino at all, and I want to build a small robot for a few sensors and speed/direction control. Is there a model that is more useful, but not overkill? It would be nice if I could standardize on one that had broad applicability. Any suggestions - and reasons for your suggestion?