All money is supposed to be changed at official banks or moneychangers, and you are supposed to be given an encashment certificate for each transaction.
The rupee (Rs.) is divided into 100 Paise. There are coins of 10, 20, 25 and 50 paise, Rs. 1, 2, 5 and 10 and notes of Rs 5, 10, 20, 50, 100 and 500.
You are not allowed to bring Indian currency into the country or take it out of the country. You are allowed to bring in unlimited amounts of foreign currency or traveler's cheques, but you are supposed to declare anything over US $10,000 on arrival.

Banks
Banks are open for transaction from 10.00 - 14.00 hrs except Saturdays (10.00 - 12.00 hrs). Major Banks are State Bank, Canara Bank, Bank of Madura, Bank of Baroda, HDFC Bank, ICICI Bank. ATM facility is available in major cities

Credit Cards
Credit Cards are widely accepted in India particularly Visa, Master Card, American Express and Diners Club.

With American Express, Master Card or Visa cards you can use your card to obtain cash rupees. With Amex you can also get dollar or sterling traveler's cheques, or get cash rupees locally from an Amex office, but you must have a personal cheque to cover the amount, although counter cheques are available if you ask for them.
Main hotels, restaurants, and shopping centers honour major credit cards.

Currency
Indian Rupee.
The approximate conversion rate is
USD 1 = Rs. 45.50