Summarize:

1. USD 1:1 collateralized stablecoins: USDT, USDC, USD1, and other giants' issued xxUSD. These stablecoins dominate the market heavily relying on background support and channels.

2. Algorithmic stablecoins: UST has already collapsed; probably no one trusts algorithmic stablecoins anymore? These stablecoins rely on complex design.

3. Over-collateralized stablecoins: Sky's USDS, originally MakerDAO's DAI, AAVE's GHO. These stablecoins are backed by DeFi protocols and are essentially underground crypto banks.

4. Delta arbitrage stablecoins: The largest is USDe; later entrants USDX, USR all collapsed.

A reminder: don't easily trust arbitrage stablecoins offering APYs higher than USDe. If they offer extra APY, the arbitrage targets are likely altcoins and small hedge or PerpDEX platforms. A sudden ADL (Auto-Deleveraging) can expose protocols to huge risks. USDe has even de-pegged before; trusting others might be "fortunate."

As for Vanisa's comment on fiat-backed stablecoins being somewhat "restrained," from a big future perspective. In the second half of the year, RWA (Real-World Asset) on-chain will still have fiat-backed stablecoins as the underlying assets, and competition in this area will be fierce.

However, USDS's issuance volume has been breaking new highs, which is a strong response to the "Clear Law" that stablecoins can't generate yield.

Stablecoins still have a long way to go—both centralized and decentralized!