Look around the room that you are in. Do you see anyone who looks exactly like you? Unless your identical twin is in the room the answer is probably no.
Have you ever wondered why we are all different? Why do you have brown eyes when your brother or sister has green eyes? Why is one of your parents tall while you are short? Why do you have light hair when your brother or sister has dark hair? The answers to all of these questions are in your DNA.
DNA, or DeoxyriboNucleic Acid, is the blueprint that makes me, me and you, you.