It is true that, nowadays, you can earn money by trading some bitcoin. However, by its nature, bitcoin is not something like that at all. Satoshi Nakamoto, its creator, has invented the system of block-chain as a way to make it possible a peer-to-peer payment system on the Internet without third-party organizations. Thus, for bitcoin to be a pioneer of a brand-new social model or to be something revolutionary, we should SEPARATELY consider bitcoin (and other virtual "currency") and currencies issued by nations.