Glossary
Merkle Proof
A compact cryptographic proof that a specific item belongs to a Merkle tree, built from the sibling hashes along the path from the leaf to the root.
A Merkle proof is the set of sibling hashes needed to recompute a Merkle root from a single leaf. A verifier hashes the leaf, combines it with each supplied sibling in order up the tree, and checks that the result equals the trusted root. If it matches, the leaf is proven to belong to the committed set — without revealing or downloading the other leaves.
Because the proof grows only logarithmically with the size of the set, light clients, rollups, and airdrop contracts use Merkle proofs to verify inclusion cheaply on-chain.