You can imagine the Blockchain as if it were a shared digital register where lists of transactions are constantly loaded.
This register is supported by a Network Peer to Peer (p2p) which can be public or private.
Each member of the Blockchain, as we said in the last article, is at the same time Server and Client, uses the same "consensus mechanism" to verify the transactions made through the Network.
This mechanism allows the constant review of transactions.
Thanks to the distributed nature of the Blockchain there is no way to change a transaction already registered unlike a centralized register such as the bank where it is possible to correct everything, even to the detriment of the customer.