Governments around the world — including the U.S., China, Japan, Canada, Venezuela, Estonia, Sweden, and Uruguay are either actively working on some form of digital currency.

But governments have very different priorities, and decentralization a main feature of most cryptocurrenices including bitcoin doesn't tend to be one of them. In fact, government digital currencies could herald a new era of centralization, posing serious questions about privacy and the viability of true cryptocurrencies like bitcoin.

There's important differences between true cryptocurrencies and what are generally called "centralized digital currencies" (CDCs). One of the main qualities if not the central feature  of cryptocurrencies is that they're decentralized. This means no single person, government, company, or group can control them. CDCs, on the other hand, are on the opposite end of the spectrum. They are as centralized as can be.