Since the beginning of the growth of digital currencies, central banks have been thinking of the consequences of such innovations. Paper money has been used for centuries and now there could be something threatening its existence. This pushes central banks to think of their future and the future of the traditional financial system. Will paper money lose in front of the digital currency? Will they have to take new steps? What is their future? In this article we will talk about 5 implications digital currencies have on central banks.