Help on Primary dealers in India

Hello,

I am looking for data on Primary Dealers in India for my specialisation project of MMS 4th semester so kindly revert back on it as soon as possible.
I want information on the following topics
1.what is Primary dealers?
2.Why Primary dealers?
3.Role and effect of primary dealers?
4.Example of any primary dealer?
5.Any statistics if availiable?

this are the main things on which i am looking information... any thing other then this will do. but primary concern is on these topics.
Thanks
Nimish

Hey i m currently doing my summer internship at hdfc bank wherein my project is on primary dealers and even i m not gettin any statistical data...
I would be grateful if u can share your research and project data. My id is