Can I use Ziddu.com?

Everyone can use Ziddu.com.

 Does it cost me anything?
 What is BitCoin ?
 Can I create Ziddu Wallet?
 How to Top-up my Ziddu Wallet?
 How can I convert my BitCoins into e-Commerce Voucher / Mobile Recharge / Game Cards?
 How can I recharge my mobile from Ziddu.com?
 What if I do not have enough balance to purchase e-Commerce Voucher / Mobile Recharge / Game Cards?
 How can I get points with Ziddu.com?