The purpose is based on the goal of creation - the formation of a monetary unit that will provide free access and independent functioning in the virtual space - the Internet. Many compare the cryptocurrency with an ordinary electronic wallet, but in this aspect there are fundamental differences.
Cryptocurrency function only on the Internet. You can withdraw them only through an exchange for fiat money - a common currency.
Accordingly, such currency is used in settlements and transactions around the world, bypassing the multilevel exchange of national currencies.