In regards to Fabric blockchain blocks.

Let’s have a closer look at the structure of a block. It consists of three sections Block Header This section comprises three fields, written when a block is created. Block number: An integer starting at 0 (the genesis block), and increased by 1 for every new block appended to the blockchain. Current Block Hash: The hash of all the transactions contained in the current block. Previous Block Hash: A copy of the hash from the previous block in the blockchain.

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