Light Node

A light node, also called a light client or SPV client, is software that interacts with a blockchain without storing its full history. Instead of validating every transaction, it downloads block headers and asks full nodes for proofs that a specific transaction was included in a block. That makes it fast enough to run on a phone or inside a browser extension, which is why most consumer wallets work this way. The trade-off is trust: a light node relies on the honesty and availability of the full nodes it queries, and it cannot independently detect every kind of invalid state. Users who need maximum assurance run a full node instead, or point their wallet at one they control.