Your head is the top part of your body, which has your eyes, mouth, and brain in it.
e.g. Sarah nodded her head in agreement.
Your hair is the fine threads that grow in a mass on your head.
e.g. I’m having my hair cut this afternoon.
Your neck is the part of your body which joins your head to the rest of your body.
e.g. She wore a scarf around her neck.
Your chest is the top part of the front of your body where your ribs, lungs, and heart are.
e.g. Susan went to the doctor complaining of chest pains.
Your back is the part of your body between your head and your legs that is on the opposite side to your chest and stomach.
e.g. Do you sleep on your back or your front?