Lets talk more about Arduino...
Arduino comes with different flavors.
You can have it as very basic and small like this one (below)... almost the same size as the chip itself.
Or you can simply just buy the parts and put it on a breadboard. Very cheap approach
or typical Arduino that you can buy pre-made like this one...
or the big sister Mega 2560 (bigger board compared to regular one). difference is the chip... What do you mean? Well bigger chip means more input/output. Which means more functions that we can assign. Which also means more expensive.
Its actually your pick.
I ended up buying "duemilanove" because its the cheapest at the time. I was looking for "uno" but they are more expensive... You will ask why not just
buy this one which is just $9 dollars. Well, I need to have a USB connection to it so I can program it easily. In other words, this one in particular needs external
USB-to-TTL FTDI-type cable or adapter to communicate.