It’s programmable, meaning you can use it for smart contracts. A common smart contract use case is dex smart contracts that let you swap between other cryptos and usd without any counterparty risk.
USDT and USDC would be the two biggest examples by market cap, though USDT has been mired in... "controversies", and USDC almost got hit by the US Banking Panic this year,
USDC definitely got hit as it depegged from the USDC for few days and traded for $0.87 at some point, it didn't "explode" (and it restored its peg) only because the US government promised to bail out customers of the Silicon Valley Bank fully and not just upto $250,000 as it would be the case if in an usual FDIC coverage situation. Circle, the company behind this stablecoin had about $3.3 billions in SVB.
