Bitcoin is a very sustainable crypto currency and this is not hypothetical as bitcoin has always proved its worth by making its existence since more than a decade and not only this bitcoin has gone through a lot in making such a tremendous success as from having millions of haters to millions of investors, the journey was never that easy and that bitcoin is on the top of crypto ranking, though most of the nation are in against of bitcoin because of its illegal use but there are few countries who has legalised crypto transactions in their nation and in the future when it will get legalise all over the world then obviously the world will be fully digital and people then need not to carry paper currency with them.