People sometimes ask me things like "What do you actually _do_ for work?" And most often I fob them off by saying something like "computer work" or if they're slightly knowledgeable I say phrases like "usability" or "human factors" or "interface design." But really, that's not what I do.
What I do is interaction design. And, while talking about interaction design is not exactly like dancing about architecture, it has some of the same problems. With that in mind, here's what I do:
I create situations in which dialogs can take place between people and products, services, and systems. These dialogs are almost always an exchange of behaviors and take place in the dimensions of time, complexity, emotion, and experience. I could not function without an understanding of thought, memory, attention, and perception. I employ the tools of simplicity, observation, and compassion to create these situations and I apply them to problems in business and popular culture. When I do my job well, complex things seem easy; things that are overwhelming become fluid. I create structures from which people extract cohesive and enjoyable results.
(I am indebted to forward-thinking interaction designers such as Jon Kolko, Bill Moggridge, and John Rheinfrank for articulating some of these things long before I tried to articulate them. And no, I can't possibly explain this to my mother.)