A matrilineal society is a society in which lineage, birthright and social classification are traced through the mother's ancestry rather than the father's, as is common in patriarchal societies. Although there were many ancient matrilineal societies, many of them have since died out.
One of the few matrilineal societies that remains is a small one within India called Meghalaya. Much of the modern understanding of matrilineal society comes from athropological studies of the Meghalaya. A key detail of the society is the favoritism of daughters over sons. This is related to the idea that the mother's familial line determines position within society, rather than the father's.