Why Are Abandoned Blocks Appearing on the Bitcoin Network and What Is Happening to Them?
According to the official terminology of Bitcoin Core, “abandoned” or “stale blocks” are those that are not part of the main chain. They can be created in a natural way when two miners produce two blocks at almost the same time, or they can be generated by an attacker in order to attack a blockchain. And “orphan blocks” refer to those blocks, the “parent block” of which is still unknown, that is, the node has not yet processed them. The community, however, often confuses these concepts, mistaking an “orphan” block for one that did not enter the main chain, because it was ahead of the other. This designation is used by Blockchain.info in particular.
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