While Tether (USDT) is one of the most popular and widely recognized stablecoins, there are other stablecoins in the market like USDC, DAI, and PAX. The main difference is the issuing entity and the transparency mechanisms. For example, USDC is issued by Circle and Coinbase and provides more frequent attestations of their reserves. DAI, on the other hand, is a decentralized stablecoin backed by cryptocurrency collaterals rather than fiat.