What is "tripundra"

Tripundra (Sanskrit: त्रिपुण्ड्र tripuṇḍra "three marks") is a Saivite tilaka, and a body art with origins in South Asia. It consists of three horizontal lines on the forehead, usually with a dot made from sacred ash, and has spiritual meaning in Shiva tradition within Hinduism. A Vishnu tradition related mark consisting of vertical lines is called Urdhva Pundra.