blocks in blockchain are the packet of information identical to each other if you change any block, then the information of all blocks are updated
what is the block in Blockchain?
the blockchain is copied and spread across a network of computers. Whenever a new block is added to the blockchain, every computer on the network updates its blockchain to reflect the change.
Each block, or data record, is digitally signed with a 'hash' – the result of a mathematical algorithm – that is based on the contents of the record and every other record in the blockchain.
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