Blockchain-based networks store digital currency transaction histories as duplicated, distributed records for all of its users. Therefore, everyone has matching copies of all the transactions on the network.
With traditional internet technology, one party holds all the records, and users can access transactions and balances stored there. Blockchain technology ensures that no single entity controls or manipulates stored transactions and that these records do not have a single point of failure. This is because distributed copies are constantly compared and updated against each other which makes it impossible for anyone to manipulate, control or steal from the network. Should one record be tampered with, the change will be corrected automatically after a comparison to the other copies on the network.
However, this form of technology does not allow everyone to see everyone else’s transactions or balances. This happens because all the transactions are encrypted using cryptographic techniques which result in transactions being nonsensical lines of random letters and numbers.
Only people with the required authorization will be able to decode transactions relevant to them by making use of their unique identification keys. This means that copies can be compared and updated against each other, but it does not hold any meaning without the proper authorization.