You friends have nothing but good things to say about you! They might not know you in the context of work, but they know your personality and your quirks very well. The interviewer wants to see how you would describe yourself. Take a moment to think about how others perceive you in social situations. They might say that you are friendly, outgoing or compassionate. When you are struggling to accomplish a goal, your friends might say that you are motivated and that you persevere through obstacles. If you're not quite sure how you would answer this question, call one of your friends! And keep in mind, there is no wrong way to answer this question. The interviewer simply wants to hear about your qualities and strengths.