Q: What are orphaned blocks?
An orphaned block refers to a block that was originally accepted by the
network (a part of the network, anyway) as a valid block with a valid
hash and valid transactions.
to the physical constraints of computers and the internet, a block that
is solved by a miner and contributed to the network is not instantly
propagated to the rest of the network. At minimum, it could take several
seconds for data to transfer around the world. Due to this potential
time lag, two miners may effectively simultaneously solve the same
block. There will be nodes geographically closer to miner A than miner
B, and vice versa, so the network will be temporarily split into two
very similar but different chains, as the nodes broadcast to one another
what they believe to be the most recently mined block.
one of the two chains will demonstrably have a greater proof-of-work
than the other, and the nodes on the other chain will update/reorganize
their blockchain records/database accordingly and begin to only accept
transactions on the chain with the greater proof-of-work.
Orphaned blocks are the legitimate blocks from the chain that lost out to the chain with a greater proof-of-work.
a transaction was reflected on the 'B' chain, in an orphaned block, but
not the 'A' chain, then once the network subsequently is fully on the
'A' chain, that transaction from the B chain will revert to being
unspent (or will have been subsequently mined on the 'A' chain). Spent
outputs do not get lost on a 'B' chain, since the history of any 'B'
chain spends is effectively erased once the network accepts the 'A'
I used 'A' and 'B' for example purposes only, with 'A' as the chain
that ends up being the "true" chain, as demonstrated by its greater