Timelock

A timelock is a condition that delays when funds can be spent or an action can be carried out on a blockchain. In Bitcoin, a transaction's locktime field states the earliest block height or time at which it can be included in a block, and script commands added through soft forks in 2015 and 2016 let coins themselves be locked until an absolute date or until a set number of blocks have passed since they were received. Timelocks are essential to hashed timelock contracts, which power the Lightning Network and atomic swaps, and to inheritance and vault setups with delayed fallbacks. On Ethereum and other smart contract platforms, timelock contracts are widely used in on-chain governance to hold approved changes for a waiting period, giving users time to review them or withdraw before they take effect. Timelocks are also used to vest team tokens.