TL;DR
A liquid staking token (LST) — like mSOL, jitoSOL, or JupSOL — represents SOL staked in a pool. It accrues staking rewards over time and can be traded or used as DeFi collateral while it keeps earning.
When you deposit SOL into a liquid staking protocol, you receive an LST representing your share of the staked pool, which delegates the SOL across validators. Most Solana LSTs use a value-accrual model: the token quantity stays the same, but each LST becomes redeemable for steadily more SOL as rewards compound — so 1 jitoSOL is worth more SOL over time.
The point of an LST is composability: your staked SOL no longer sits idle. You can lend it on Kamino, LP it on Orca, or post it as collateral on Drift while it keeps earning the underlying staking yield — letting you stack DeFi yield on top of staking rewards.
An LST adds smart-contract risk on top of staking, and can briefly trade below its underlying SOL value (a depeg) when exit liquidity is thin. The native redemption value stays intact, so a depeg mainly hurts if you must exit instantly during the dip. The major LSTs (mSOL, jitoSOL) are well-audited with deep liquidity.