Staked Ether, or STETH, is a type of cryptocurrency token that represents Ether (ETH) that has been staked in the Ethereum 2.0 Beacon Chain. It is a part of the Lido decentralized finance (DeFi) project, which enables users to earn rewards from staking without needing to run their own Ethereum 2.0 validator nodes.

The Lido Project Lido is a decentralized Ethereum 2.0 staking solution. It aims to solve the challenges of staking in the Ethereum 2.0 network by offering liquidity for staked ETH. With Lido, users can stake their ETH without minimums or needing to run their own infrastructure while receiving STETH tokens that represent their staked ETH and the rewards it earns. Lido allows holders of STETH to benefit from the potential increase in value of staked ETH while also maintaining some liquidity.

STETH tokens represent staked ETH in the Lido protocol. Holders of STETH receive a proportionate share of the staking rewards generated by Lido validators. The STETH tokens themselves can be traded, used in DeFi applications, or held in a wallet to continue earning staking rewards.

In other words, STETH gives holders the ability to earn rewards from staking in the Ethereum 2.0 network while also providing them with a liquid token they can use within the wider Ethereum ecosystem.