Bitcoin should be used as a common currency, international payment means no "gold guarantee" regime, as Bitcoin is now gold. And the use of Bitcoin as the currency for the whole world makes businesses no longer have to face the risk of exchange rates, transaction costs also dropped to very low.
Bitcoin copper faces many of the same challenges as gold. Gold does not, by itself, pose a risk of price change, but it is easy to be robbed during shipping. In the past, gold was often robbed on the trade routes, Bitcoin can be "robbed" on the Internet.