Hash
Also known as: Hash Output, Cryptographic Fingerprint, Digital Hash
A fixed-size alphanumeric output derived from input data using cryptographic algorithms, foundational to blockchain integrity.
A hash is a cryptographic output generated by applying a hash function to input data of any size, producing a fixed-length string. It acts as a digital fingerprint for data, ensuring integrity and immutability. Hashes are fundamental in blockchain to link blocks, verify transactions, and secure data. Common hash functions include SHA-256 (used in Bitcoin) and Keccak-256 (used in Ethereum). Even small input changes result in drastically different hashes, a property called the avalanche effect. Hashes are also used in digital signatures, mining, and content addressing (e.g., IPFS).