The Arduino is a micro-controller platform for entry level embedded systems applications.
Ok. Take two:
The Arduino is like a computer on a single chip. What makes it cool is that you can attach switches, lights, knobs, speakers, lasers, and monkeys to it.
Yes. Even monkeys. Or humans. Or.. well.. ANYTHING.
What makes it +6 awesome is that writing software for it is actually pretty easy (unlike other micro-controller platforms).
This class will introduce you to the Arduino hardware, as well as the software IDE.