Why is the file called the “blockchain”? 5/n

As we have seen, transactions are not added to the file individually – they are collected together and added in blocks. Each of these new blocks?builds on top of?an existing one, and so the file is made up of a?chain?of?blocks; hence,?blockchain.

The blockchain is a file of?transactions. It’s the most significant file that a bitcoin?node?maintains.

It is called the “blockchain” because new transactions are added to the file in?blocks, and these blocks are built on top of one another to create a?chain?of blocks. Hence, blockchain.

But ultimately, the blockchain is?permanent storage for bitcoin transactions.

Furthermore, every node on the network?will always adopt the?longest chain?of blocks they receive?as the “official” version of the blockchain. This means that miners will always try to build on top of the “tip” of the longest known chain of blocks, as any blocks that are not part of the longest chain will not be considered valid by other nodes.

Therefore, if someone wanted to rewrite the history of transactions, they would need to rebuild a longer chain of blocks to create a new longest chain for other nodes to adopt. However, to achieve this, a single miner would need to have more computer processing power than the rest of the network combined.

As a result, the combined effort of the network makes it difficult for any individual to “outrun” the network and rewrite the blockchain.