Commitment hash

A hash over the exact inputs, factors and result of a calculation, so the same inputs always produce the same value.

A commitment fixes a calculation in place. Recompute with identical inputs and factors and you get an identical hash; change anything and it changes.

What it proves is reproducibility: this result follows from these inputs. What it does not prove is when the calculation happened — for that the commitment has to be anchored to something with an independent timestamp.

The distinction is worth keeping straight, because the two are often described together and only one of them is present in most systems.

Merkle proof A short cryptographic path showing that one record belongs to a set, without revealing the rest of the set.
Anchoring Publishing a hash to an independent, append-only ledger so that a record can later be shown to have existed unchanged.
Verifiable, not verified A record anyone can check for themselves is not the same as one an accredited body has audited. Both are useful; they are not interchangeable.