The Architecture of Trust
Merkle Tree
A hash-based tree structure enabling tamper-evident verification of large data sets — change one byte and the root hash changes irrecoverably.
Definition
A cryptographic data structure in which every leaf node is labelled with a hash of its data and every non-leaf node is labelled with the hash of its children. The Merkle tree allows efficient, tamper-evident verification of large data sets: change a single byte anywhere in the structure and the root hash changes irrecoverably. In blockchain systems, Merkle trees are the mechanism by which a lightweight client can verify that a transaction exists without downloading the entire chain.