The terms "geek," "nerd," and "hacker" arise frequently in my work and settling upon a common understanding of these words is a challenge: each has varied meanings and they are sometimes used interchangeably. However, I try to use them distinctly. A hacker uses significant technical proficiencies to explore and build complex systems. (This is in the broadest sense and not in the pejorative sense associated with criminal activity.) A nerd is characterized by a person who prefers narrow, intellectual pursuits to broader social and physical activities. (So "computer nerds" are a subset of nerds.) A geek has a passionate enthusiasm for some particular interest that may eclipse other life activities. (That is, one can "geek out" about most any topic.) In my own usage, unless otherwise specified, I freely use the term "geek" in the online context. For example, a "reef geek" is into aquariums, but otherwise to speak of "geekdom" or being "geeky" implies some aspect of online activity.