This is a quote from the book "Bitcoin: A Peer-to-Peer Electronic Cash System" by Satoshi Nakamoto
... on finding a difficult proof-of-work for its block.When a node finds a proof-of-work, it broadcasts the block to all nodes.Nodes accept the block only if all transactions in i
t are valid and not already spent.Nodes express their acceptance of the block by working on creating the next block in the chain, using the hash of the accepted block as the previous ha
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Nodes always consider the longest chain to be the correct one and will keep working on extending it. If two nodes broadcast different versions of the next block simult...