Hash
Quick Answer
A hash is a fixed-length string from a cryptographic function used as a unique transaction identifier. Transaction hashes are used to track and verify payments on block explorers.
Full Definition
A hash is a fixed-length alphanumeric string produced by a cryptographic hash function from variable-length input data. Hashes are one-way — you cannot reverse-engineer the original data from the hash. In blockchain, every transaction and block has a unique hash that serves as its identifier. Transaction hashes (TxHash or TxID) are used to track and verify payments on block explorers. Hashing ensures data integrity across the entire blockchain.
Related Terms
Hardware Wallet
A hardware wallet is a physical device that stores cryptocurrency private keys offline, providing maximum security. Leading examples include Ledger and Trezor.
Hot Wallet
A hot wallet is an internet-connected cryptocurrency wallet for frequent transactions. Payment processors use hot wallets for operational liquidity needed for daily settlements.
HTLC (Hash Time-Locked Contract)
An HTLC is a smart contract requiring payment acknowledgement within a set time window, enabling trustless cross-chain swaps and payment channels like Lightning Network.