A nuclear family is a family group consisting of only a father and mother and their children, who share their dwelling.
Nuclear families can be of any size, as long as they are parents and there own children.
Joint family:
This consists of members of 3-4 generations living under the same roof.
All the male members are blood relatives and all the women are mothers, wives, daughter in-laws and unmarried daughters.
The joint family status being the result of birth, possession of joint cord that knit s the members of the family together.
The family in India is mostly headed by a patriarch, usually the oldest male, who makes decisions on economic and social matters.
Extended family:
An extended family group is immediate family members living together with extra-nuclear family members such as grandparents, aunts and uncles, cousins, and nieces and nephews.
An extended family may live together as a single household.
Often there could be many generations living under the same roof, depending on the circumstances.