They’re cryptographic currencies issued and controlled by central banks. Very similar to cryptocurrencies, but they’re centralized and fully controlled by the issuer. Check more here.
I'm a literature professional in the crypto world since 2016. It doesn't sound very compatible, but I've been learning and teaching about blockchain and cryptos for international portals since then. After hundreds of articles and diverse content about the topic, now you can find me here on Alfacash, working for more decentralization.