<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>

CC BY-SA 4.0
2019-08-21T15:56:53.303Z
All right now I think I understand. Does that also mean that a light node saves the chain of the block headers and a full node saves the whole blocks?
evannemo
CC BY-SA 4.0
2019-08-21T16:41:51.780Z
@evannemo Yes that is correct. SPV nodes store the block headers of all the blocks which is how they can verify that a transaction is included in the block when they are provided with a Merkle path by connected full nodes.
Ugam Kamat
CC BY-SA 4.0
2019-08-21T16:50:33.153Z
@UgamKamat Can you explain this a little further? What is a merkle path? And how is this verification done? I have opened a new question, if you think you can explain it in details please have a look here: https://bitcoin.stackexchange.com/questions/89854/what-is-the-complete-process-and-purpose-of-a-block-validation-using-merkle-tree
evannemo
CC BY-SA 4.0
2019-08-21T15:55:00.243Z
2019-08-21T15:55:00.243Z
Raghav Sood
<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>

<merkle-tree>
Question about Merkle trees and blocks
evannemo
# Question about Merkle trees and blocks

(Asked by: username_0 on 2019-08-21)

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.

**Tags:** merkle-tree


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## 1 answers

### Answer by username_1 on 2019-08-21. Score: 1 | Accepted answer

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

> **Comments:**
> **username_0**: All right now I think I understand. Does that also mean that a light node saves the chain of the block headers and a full node saves the whole blocks?  
> **username_2**: @username_0 Yes that is correct. SPV nodes store the block headers of all the blocks which is how they can verify that a transaction is included in the block when they are provided with a Merkle path by connected full nodes.  
> **username_0**: @username_2 Can you explain this a little further? What is a merkle path? And how is this verification done? I have opened a new question, if you think you can explain it in details please have a look here: https://bitcoin.stackexchange.com/questions/89854/what-is-the-complete-process-and-purpose-of-a-block-validation-using-merkle-tree  

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