I have trouble explaining what I do to most adults, so when my five year old daughter asked me what I did for work, I came up with the simplest explanation I could find: "I sell computer chips."
She paused a moment. "Do they taste good?"
I guess I deserved that. My daughter knows what a computer is, but to her a chip is still a Pringle.
The other thing I have a hard time explaining is the fact that I alternatively home office or leave on the road for long periods of time. She gets it when I have "to go to work on a plane" and have to be away from home for a "long time" (any period of time over two days is long time to her), but "working from home" is still a hard concept for her to grasp. But most of corporate America has the same problem, so she is not alone there.