USDT, or Tether, is a type of cryptocurrency known as a stablecoin. Stablecoins are designed to maintain a stable value by being pegged to a reserve asset, such as a currency like the US dollar, a commodity like gold, or another cryptocurrency. In the case of USDT, it is pegged to the US dollar, meaning 1 USDT is intended to be worth 1 USD. This stability makes USDT useful for trading, remittances, and as a store of value in the volatile cryptocurrency market.