The answer to this question shapes how we see ourselves and how we present ourselves to others. Sociologist Charles Cooley characterized the self as a looking glass. By this he meant that we learn who we are by the feedback ,or reflections, we get from others. The self is socially constructed in interaction with others. How we see ourselves encompasses both personal and social identities.
Personal identities are categories unique to an individual, such a name, birth date, birth place.
If you want to read more about identities, here are some resources to get you started.