Define ‘Block Header’ in the Context of a Blockchain.

A block header is a crucial data structure at the beginning of every block in a blockchain. It contains metadata about the block, including the previous block's hash, a timestamp, the Merkle root of all transactions within the block, and the nonce.

In Proof-of-Work, miners compete to find a nonce that, when combined with the other header data, produces a hash below a specific target. This successful hash links the block to the chain and validates the block.

What Is the Purpose of a ‘Timestamp’ in the Block Header?
Does the Timestamp Affect the Hash of the Merkle Root?
How Does a Pool Operator Detect ‘Share Hijacking’?
What Is the Role of the Merkle Root in a Block Header?
What Is the Difference between a “Block Header” and the Full “Block Data”?
How Does a ‘State Root’ in Ethereum Compare to the Merkle Root in Bitcoin?
How Does a ‘Light Client’ Utilize the Merkle Root for Verification?
How Is the Nonce Related to the Block Timestamp?

Glossar