Why Is the Merkle Root Essential for Simplified Payment Verification (SPV)?

Simplified Payment Verification (SPV) allows a light client (wallet) to verify that a transaction is included in a block without downloading the entire blockchain. The light client only needs the block header, which contains the Merkle Root, and the Merkle path (a small set of hashes) from the transaction up to the root.

By re-hashing the path and checking if it matches the Merkle Root, the client can cryptographically prove the transaction's inclusion and validity.

How Does a Lightweight Wallet Use the Merkle Root for Verification?
Why Is SPV Less Suitable for Verifying the Full State of a Smart Contract Platform?
What Is a SPV Client and How Does It Use the Merkle Root?
How Do ‘Simplified Payment Verification’ (SPV) Wallets Use Merkle Trees?
How Does a Merkle Root Verify a Transaction without Exposing the Entire Block?
How Does a ‘Merkle Tree’ Relate to Off-Chain Data Verification?
What Is a ‘Light Client’ and How Does It Utilize the Merkle Root?
How Does a Block header’S Merkle Root Relate to the Immutability of the Block’s Transaction Data?

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