The watt (W).
Bandied about in conversations regarding anything from car-stereo speakers to nuclear reactors, we take it for granted as self-explanatory. But is it? Just in case you are unfamiliar with the term and its usage, here's a breakdown a-la Wikipedia:
Since diving into the deep end when it comes to energy issues, almost every day sees new fascinating concepts, approaches, and technologies. Fascinating ... exciting ... even hope inspiring at times. And, as well, as the passion builds, so many of these are truly Energy COOL.