up until now i dont know if bitcoin can be categorized as currency,,it just commodity without physical like gold..
if bitcoin a currency there there will be a paper bitcoin,,or anything that has physical..
Bitcoin is a digital currency and that is known and told by everyone. Is a particular new currency which for the moment have no physical form. I write "for the moment" because in the future it is not impossible that even bitcoin has its physical form.
But it is not the problem about which I want to discuss in this thread.
Let's make an analyse of your post. You tell that if bitcoin be a currency there will (must) be a paper coin, or anything that has phisycal (form). Where have found you this? Who told this?
Below are the meaning of the words "currency" and "money" taken from good sources. In no one of definitions is conditioned the existence of a currency with the having of one physical form of it. It is only one part of definition which ask for the physical form of the currency but this definition is not an condition but optional because tell: "
You'll need some cash in local currency but you can also use your credit card" So you need to have some cash (physical money) OR you can use your credit card. As a conclusion. If you have the credit card you don't need the cash. If you have the credit card you may "forget" about the cash. Credit and debit card with bitcoin are to many in circulation so this part of definition meet the conditions asked by the definition of the currency.
Read below the entire definition and the source of those.
According to Oxford dictionary: "The currency is the system of money that a country uses:
trading in foreign currencies
a single European currency
You'll need some cash in local currency but you can also use your credit card."
Source:
http://www.oxfordlearnersdictionaries.com/definition/english/currencyAccording to Wikipedia: "Money is any item or verifiable record that is generally accepted as payment for goods and services and repayment of debts in a particular country or socio-economic context, or is easily converted to such a form."
Source:
https://en.wikipedia.org/wiki/MoneyThe final conclusion. Bitcoin is a currency even with the actual definitions of this "tool".
But even is not. Who told you that the definitions cannot be improved with the evolution of the "tool"?