What do you do?
The industrial economy makes it easy. You can say, "I am a designer at Google" or "I am an investment banker" and the problem is solved, and the tension is relieved. Rather, there was no tension to begin with.
But, when you do work that matters, when you work on projects, when you can't hide behind a designation or a brand, then this question can create an existential conundrum. We start thinking, "What exactly do I do?"
When we try to explain the change we seek to make, it seems much more lengthy and complicated than the other person is willing to listen. And no matter how much we try, we aren't able to box ourselves into, "I am this at that".
We are complex, social and intellectual beings, and instead of trying to find an easy answer, we can choose to reframe this question to "Which projects are you working on right now?"