We have now defined and described blockchain. Now let's see how a blockchain actually works. Nodes are either miners who create new blocks and mint cryptocurrency (coins) or block signers who validates and digitally sign the transactions. A critical decision that every blockchain network has to make is to figure out that which node will append the next block to the blockchain. This decision is made using a consensus mechanism. The consensus mechanism will be described later in this chapter.
Now we will look at the how a blockchain validates transactions and creates and adds blocks to grow the blockchain.
