Stablecoins are tokens whose exchange rate is most often tied to the exchange rate of the US dollar or other asset: fiat, resource, or digital. 

All existing stablecoins can be divided into three types:

1. fiat-backed, which are backed by traditional fiat currencies (dollar, euro, yuan, etc.) or other assets (gold, oil);
2. crypto-backed ones, which are backed by other, most expensive, cryptocurrencies (bitcoin, ether);
3. algorithmic, the stability of which is ensured by smart contracts that regulate the issue of tokens.