Bharata Natyam is essentially a solo dedicatory dance. A dance dedicated to the Gods. Bharata Natyam was originally performed in South Indian Temples by those who served the Gods, the Devadasis.
Historically it has been the most exclusive classical dance Art of India. The principles and technique of Bharata Natyam were systematised and codified nearly 3000 years ago in Bharatas Natya Sastra treatise of dance.
With regard to the technique and todays contemporary form of presentation, the most applicable comparison to Bharata Natyam is Classical Ballet although the spectrum of movements and the narrative contents of the dance are fundamentally different. The actual repertoire of Bharata Natyam was conceived by four famous music composers from Tanjore, the Tanjore Quartet in South India. It comprises abstract and narrative dance compositions which follow a particular sequence. Nritta, which is the abstract or pure aspect of the dance, consists of axial geometric movements illustrating the beauty of either tala (measure of time, i.e. rhythm) or both thala and raga (melodic mode). Each pure dance sequence is entirely planned according to the thala system of South Indian Carnatic music.
The narrative aspect of the dance is called nritya and its medium of expression is called abhinaya. It consists of facial expressions, body postures and hastas hand gestures or mudras used to describe the poetical and lyrical content of the musical composition with symbolic movements and expressiveness. It enables the dancer to portray the emotions expressed in the song, thus giving the rasika (audience) privileged moments of aesthetical bliss during which its members identify themselves with the lyrics of the songs mostly based on love themes.
"These songs have their origins in Hindu mythology, literature and philosophy. They symbolise the yearning of the human soul for union with the absolute. Bharata Natyam is a composite art. It is at the same time the art of the stage, drama, music, poetry, colour and rhythm. Its keynote is the dance which includes all the arts but the message of which is not merely given to the senses, and through them to a purely external form of enjoyment, but to the soul of the dancer and of the perceiver." - Rukmini Devi
The beauty of this dance form achieves its fullest expression only when there is an effervescence of Bhava (emotion) and when Abhinaya (mimetic facial expression) projects fittingly the sentiments expressed in the songs and through the medium of music.