user97854: There is something I cannot understand about Merkle trees. I understand how they are calculated and etc., but I cannot understand how they are used on a blockchain. If a block stores only the Merkle root, how can a blockchain explorer let you search and view specific transactions? I think this requires that a block must store the whole array of transactions, not just the Merkle root. Please help me understand this. Thanks in advance.

user7272: The block header contains the merkle root, but the full block itself contains all the transactions, in order of their appearance as merkle leaves.

97854: <p>There is something I cannot understand about Merkle trees. I understand how they are calculated and etc., but I cannot understand how they are used on a blockchain. If a block stores only the Merkle root, how can a blockchain explorer let you search and view specific transactions? I think this requires that a block must store the whole array of transactions, not just the Merkle root. Please help me understand this. Thanks in advance.</p>
 7272: <p>The block <em>header</em> contains the merkle root, but the full block itself contains all the transactions, in order of their appearance as merkle leaves.</p>
