When asked, "who are you?", many people will reply with "I work at IBM," or "I live in Detroit," or "I write software," or "I come from Wisconsin." But these answers don't really address the question. (You may recognize the comedy bit from the movie "Anger Management".) If you tell me what you do, or where you live, that doesn't really tell me who you are.
In Denmark, in the 1840's, the philosopher Soren Kierkegaard struggled with this question. He decided that the real answers to these questions lay in the meaningful and significant choices you make. Who you are is shown by how you make decisions, and the most consequential decisions are made in the context of relationships. Kierkegaard would happily grant that, if you are standing by yourself in front of a machine, faced with the question of "Coke or Pepsi?", you can indeed make a free choice; but it is not a significant choice. The meaningful decisions are those which impact other humans, and which impact your relationship to those other humans. Those decisions reveal who you are.
So Kierkegaard would answer the question "who are you?" by saying, "I am a friend, a brother or sister, a son or daughter, a neighbor, etc." The answer to "who are you?" is not found in your education, your job, or your athletic record. It is found in the way you interact with other humans. Granted, you may interact with them in the course of your job, your education, or your athletic involvement.
Kierkegaard also points out that the ultimate relationship is one's relationship to God. The manner in which you deal with God shows something about who you are. Kierkegaard is known as the founder of existentialism.
