Verifying data in block headers
Each node in the Bitcoin network independently verifies Bitcoin transactions.
When verifying transactions, there is a built-in mechanism where only the block header needs to be verified.
The assumption is that not all nodes keep only the block header data.
Some nodes keep not only the block header data but also all the past transaction records.
This node is called a full node.
Even if the past transaction records are tampered with, the existence of a full node that retains all the correct transaction records can detect the fraud.
However, there is no possibility that the full node itself will be fraudulent.
Therefore, if a node really wants to keep the Bitcoin network in good shape, it should become a proper full node itself.
Check your achievement
Click the “Tick” button
if you understand the lesson so far.