A Beginner's Guide to Digital Currencies and the Blockchain - страница 20

Chapter 2: How Does Blockchain Work?

So how exactly does a blockchain work? When a transaction is made, it is broadcast to the network of nodes. These nodes then verify the transaction, checking to ensure that the sender has the necessary funds and that the transaction is valid.

Once a transaction has been verified, it is added to the block that is currently being processed. This block is then added to the chain of blocks, creating a permanent record of the transaction.

But what happens if someone tries to alter a transaction that has already been added to the blockchain? This is where the concept of "consensus" comes in. In order for a transaction to be added to the blockchain, it must be accepted by a majority of the nodes in the network. This ensures that any changes to the blockchain must be agreed upon by the majority, making it difficult for a single entity to manipulate the record.