Note Commitment

A shielded "note" is Zcash's private equivalent of a transaction output — it records an amount and an owner, encrypted so only the recipient can read it. When a note is created, the network doesn't record the note itself; it records a note commitment, a value that cryptographically binds to the note's contents without exposing them.

Note commitments accumulate into a running tree that every full node maintains. Later, spending that note requires proving — via a zero-knowledge proof — that a matching commitment already exists in that tree, without revealing which one. A note commitment on its own reveals nothing about the note's amount, owner, or purpose.