Now the world has changed. Now there is a new way of trading. In the past we used to trade by barter system. Then gold coins took its place and people start trading in gold. Then paper currency become the tool of trade of trade. In the u coming years crypto currency or electronic curreny will take over paper currency. The benefit of this currency is that it has no link with the bank. We donot have to open accounts to safe our money, because no one can steal it. Witg the passage of time the world is becoming a lot better world.