Actually there are both pros and cons of having a credit card.
It actually makes you spend more than what you can actually spend because we tend to make up our mind that no matter what I can make the CC bill payment the moment I get my salary.The CC banks make a lot of money when someone defaulters while paying the money back to them. There is late payment fee (which is around Rs. 500 for most CCs), then they levy interest, rate of which is also too high.
CC is useful in case of making online transactions (rail/airline booking, purchases etc.). But your HDFC Bank account gives you facility to create virtual CC which could be used for online transactions. It is just that you will not be able to make any purchases personally/being physically present in a shop. But your debit card will help you that time.
I dnt want to sound like an hypocrite but I will tel you that I have 6 different bank's CCs. I use them from time to time as I do not like to carry a lot of cash but I keep a tab on how much purchases I have made.