Knowing who you are is just as important than where you came from, or whom you were birthed. A lot of people identify with their occupation, or what they do for money, as to answer this question. Sometimes it depends on who your audience is, on what your response will be. If you are looking for a job, then you would focus on your primary area of interest in your occupation. So I might say that I am a writer, or a web designer. If I an talking with a colleague I might call myself a human resource authority.
Although sometimes I like being introduced as “my friend” rather than an occupation. It’s natural for people to tell something about their new friend, and usually it is meant in good will with positive intentions. Many times you might be in a social situation where you job isn’t relevant at all. Sometimes your skills or talents might help set you apart when being introduced. When I was younger, I would go to raves. My friends would always tell people I was an awesome raver/dancer and to look out for me later in the night. When I sang in the choir, I was always known as Tenor Aaron.
You are only limited by your imagination.