Banis of Bharathanatyam

Bani or tradition is a term used to describe the dance technique and style specific to a guru or school.  Banis are usually named as the village of the guru , even though exceptions are there.
Bharathantyam which was also known as Sadir,  originated from Tamilnadu and was practiced by Devadasis .Even though it was banished , by the Britishers, the Tanjore quartet Chinnaih, Ponnaiah, Sivanandam and vadivelu re-edited and refined the dance form.The major descendants of Bharathantyam are Nattuvanar parampara and Devadasi parampara.

Major banis include Tanjore, Vazhuvur, Pandanallur,Kanchipuram,Tiruvidaimaruthur, Karaikkal etc..The naunces in these styles are very subtle.The salient features of different styles are listed below:

Tanjore:

• Nritta and Nritya elements are blended in an equal proportion
• Deep sitting postures combined with adavus and theermanams
• Emphasis on Sringara abhinaya

Vazhuvur style:

• Wide range of dancing pace
• Static postures are inserted, most often in the thillana, to break the monotony and to add  the variety of rhythms
• Soft facial abhinaya
• Abhinaya is more subtle with natyadharmi, so that it is not overdone
• Smooth flow of adavus
• Extremely elaborate movements
• Deep sitting positions
• Variety of positions on floor
• Rich sringar element
• Lasya dominates thandava
• Dancers body from the waist up is slightly bent forward
• Leaps are introduced into every jathi
• More karvais or intervals in jathi
• Performanace begins with Thodaya mangalam
• Entrance of the stage from the wings

Pandanallur style:

• Deep sitting positions
• Predominantly Padartha abhinaya
• Its Lasya of padams is rather slow and difficult to perform
• Performed in 3 levels: 
• Deep sitting levels
• On the ground
• Standing positions
• while moving or jumping
• Broad sweeping movements

Kanchipuram/BalaSaraswathi

• Emphasized the precision of basic stances
• The rhythmic tempo and subtleties of abhinaya

Tiruvidaimaruthur

Famous triplet Lalith Ragini padmini were the propogators of this style

Karaikkal:

• Uncanny sense of laya making the technique vibrant
• Combination of intricate and tough nuances of rhythm
• Powerful grip in reciting the laya and clear theermanams
• Juxtapositionig forward movements with diagonal palcements/side movements and warming up the empos gradually

Kattumannar Kovil Bani:

• Less Jump and more footwork
• Erect posture
• Pure and clear arm movements which were firm without being right and left and rounded without being slippery

Mysore School:

• Use of Sanskrit slokas in abhinaya

Other than these banis there are kalakshetra Bani and Kalamandalam style of bharathanatyam.A dancer can select any of these banis without changing the basic structure of the dance form.

Courtesy: Sandhya Ramakrishnan's paper on different Banis of bharathanatyam.