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 sh.

  • 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...
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