BETH is an equity certificate in ETH 2.0 staking process. With it locked ETH can be redeemed for the equivalent value, as well as rewards from locked ETH can be obtained. With the advanced ETH 2.0 more interests may be granted.
vETH and aETH are the Polkadot's cross-chain project Bifrost, and ETH Staking service platform Stkr developed by Ankr launched ETH 2.0 staking equity certificate, similar to BETH, but service is carried out in a decentralized manner. In addition, it can be 1:1 with BETH. Unlike the similar redemption of locked ETH, the value of vETH and aETH will be determined by the market.