Tilak (Vaishnava)
Overview
 
Followers of Vaishnavism
Vaishnavism
Vaishnavism is a tradition of Hinduism, distinguished from other schools by its worship of Vishnu, or his associated Avatars such as Rama and Krishna, as the original and supreme God....

mark their foreheads with different styles of tilak to show that they are servants of Vishnu
Vishnu
Vishnu is the Supreme god in the Vaishnavite tradition of Hinduism. Smarta followers of Adi Shankara, among others, venerate Vishnu as one of the five primary forms of God....

. The markings are made either as a daily ritual, or on special occasions, and denote which particular lineage, or sampradaya
Sampradaya
In Hinduism, a sampradaya can be translated as ‘tradition’ or a ‘religious system’, although the word commands much more respect and power in the Indian context than its translations in English does...

the devotee belongs to. The different Vaishnava sampradayas each have their own distinctive style of tilak based on the siddhanta
Siddhanta
Siddhanta, a Sanskrit term, roughly translates as the Doctrine or the Tradition. It denotes the established and accepted view of a particular school within Indian philosophy.-Hindu philosophy:...

 of their particular lineage. The general tilak pattern is of two or more vertical lines resembling the letter U, which commonly represents the foot of Vishnu.
In the Vallabha, Rudra-sampradaya the tilak worn is a double vertical red line which is rounded from base.
 
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