A hash tree that commits a block header to every transaction in the block.
Merkle tree is best understood as part of a system rather than as an isolated definition. Its related coordinates show the mechanisms, incentives and historical records that give the term practical meaning.
Merkle tree sits between protocol rules, economic incentives and software operated by independent participants. In Bitcoin, no component is authoritative by itself: miners propose history, fully validating nodes enforce validity, and users decide which rules and software they accept.
Understanding Merkle tree helps distinguish a verifiable Bitcoin mechanism or historical record from slogans, products and market narratives.
For the clearest picture, read this entry together with Block, Transaction, Block header. The reverse links also lead from Block header, Proof of reserves, Ralph Merkle.
Linked to related atlas coordinates
Grounded in a source record
Explains function and trade-offs
Part of the open Bitcoin knowledge graph