Lineage is understood as a principle on the basis of which alignment or inheritance is chosen in a linear fashion. Such an arrangement is called a line or lineage. Most common forms of which are patrilineage and matrilineage. It gives rise to descent groups that are linear in character. It also refers to a particular type of kin group ( Kula in Indian system) in which members have a common ancestor whose identity is known and who is generally considered as the founder of the group. In lineage, the common ancestor of lineage members is usually an actual remembered person. In case of lineage, one can trace one’s ancestors whereas in case of descent one often fails to trace one’s ancestors and the ancestor could be substituted by a mythical one symbolizing the origin of one’s descent.
Descent and lineage are often used interchangeably as well in conjunction to mean similar things for discussing kinship. Descent is the principle whereby a person is socially affiliated with the group of his or her parents, grandparents and so on. The individual belongs simultaneously to several descent groups – those of two parents, the four grand parents, the eight great grandparents and so on. If this chain is not limited, decent principle will virtually connect everyone in this world into a single descent group. However in reality some restrictions are placed to limit the size of the descent groups. Sometimes a common known ancestor can be the cut off and sometimes it can be in form of some other symbol.Descent can also be traced to some mythological figure as well. It is a method of limiting the recognition of kin group on the basis of common identity and in different societies ,different principles might be used. The possible ways of transmission of descent group membership from parents to children.
Unilineal- Descent is reckoned through a single line and it is pre-defined for an individual to which descent group will one belong. This system is followed in most parts of India. It may have further two classifications – Patrilineal where descent is traced in the male line from father to son and Matrilineal where descent is traced in the female line from mother to daughter.
Double (duolineal or bilineal) –where descent is traced in both the father’s line as well as mother’s line for different attributes such as movable property in one line and immovable in another.
Ambilineal (cognatic) – Ambilineal rule affiliates an individual with kinsmen through the father’s or mother’s line. Some people in societies that practice this system affilineate with a group of relatives through their fathers and others through their mothers. The individuals can choose which side he or she wants to affiliate to.
Parallel descent – It is a very rare form of descent where descent lines are sex specific. Men transmit to their sons while women to their daughters.
Cross or alternative type descent – It is also very form of descent where men transmit to their daughters and women to their sons.
Descent groups can be different types. Most common is family which is also the smallest descent group. A number of families are linked by a common ancestor whose identity is known form a group called lineage. A number of lineages linked together with a common ancestor whose identity is not known is called clan or gotra in India .It is exogamous. A number of clans having a common mythical ancestor form a phratory and it is an endogamous group.Phratory is equated with caste in India.Descent groups perform rituals on the occasions like birth and marriages etc. Lineage and kinship are instrumental in defining the identity of a person and distinguish between insiders and outsiders. In earlier times according to Evans Pritchard ,kinship groups could convert into war groups.The descent group will have a built in authority struture with power normally exercised by senior males.Rules of inheritance tend to be in line with the reckoning of descent in most societies.An individual's economic rights and responsibilities will be defined by his or her position in the descent group.In many societies unilineal descent groups are also jural units internally deciding their own disputes and externally acting as a unified group in the conduct of feuds ,fights etc.