I imagine it used to be somewhat easier, when most people followed a trade – in many cases that of their parents (I know I’m simplifying this a lot).
“What do you do son?”
“What do you mean dad? I spend all day working in the same bakery where you taught me my trade.”
Of course it’s all a little more complicated now. When you’re just as likely to work in a field completely alien to what your parents do as you are to do anything they’d understand. This is the theme of a series of short films by Lernert & Sander, in which artists attempt to explain to their parents what it is they do. There appears to only be one of them up there at the moment, have a look at the video below or check out the project page: How to explain it to my parents.