Final answer:
A surname refers to a person's last name or family name, passed down from their father's side in most cultures. In patrilineal societies, only males carry on the family surname, giving them permanent family membership.
Step-by-step explanation:
A surname refers to a person's last name or family name, which is passed down from their father's side in most cultures. In patrilineal societies, such as rural China and India, only males carry on the family surname, giving them the prestige of permanent family membership. However, in some cultures, like rural China, people might change to the mother's surname.