Traditional Dance Elements
Films before 1960 tended to draw heavily on classical and folk dance. Since neither "classical dance" nor "folk dance" are homogenous entities, one naturally expects to find considerable variations. Not surprisingly, early films from south India tended to show a lot of influence from Bharat Natyam and Kuchipudi while Hindi/ Urdu films tended to show strong influences of Kathak or the "mujara" dances that were associated with the tawaifs. Although these influences continue today, they seem to have become mixed with many more dance styles and have at time become unrecognisable as to their origins.
Why is dancing so crucial to Bollywood films?
People in India have been brought up on musicals and if the music in a film isn't very good, sometimes the movie doesn't sell. Specific producers, such as Yash Chopra, Karan Johar generally produce movies with phenomenal and very emotional songs; hence the dancing comes into play. Choreographers are now starting to take the industry by storm because Farah Khan – a famous choreographer recently directed her first movie called Main Hoon Na. This goes to show that people want to see elaborate and funky dance sequences, they don't want pure acting, hence dancing is a crucial.