Origin and lineage
Bharatanatyam evolved from the Sadir tradition of the temples of Tamil Nadu. In its modern form it draws from the Bharata Muni's Natya Shastra and the codifications of Rukmini Devi Arundale's Kalakshetra and the Pandanallur, Vazhuvoor and Tanjavur banis.
How a class is structured
A standard Margam progression begins at Adavus (the basic step vocabulary), moves into Alarippu, Jatiswaram, Sabdam, Varnam, Padam, Javali and culminates in Tillana. Each item demands a different proportion of rhythm, expression and theatre.
Why people learn it
For children it builds posture, focus and discipline. For teenagers it becomes a competition advantage and a route to school cultural fests. For adults it is a return to lineage, a way of staying connected to a tradition that travels with the diaspora.