Theoretically, every blockchain ledger is tamper-proof. There are many ledgers in the global monetary system that we now use. At their foundation, banks and credit card firms are simply ledgers; they record transactions and the flow of money between parties. Unfortunately, the high danger of fraud and information tampering frequently puts the traditional banking system under pressure.
This is where tamper-proof ledgers or blockchain technologies are useful. The release of the Bitcoin whitepaper marked the beginning of the first fully successful tamper-proof ledger.
In essence, node operators who validate transactions and subsequently add new blocks to the chain are actively discouraged from altering the records because a modification of this nature will be obvious. All Bitcoin node operators validate transactions based on the same copy of the ledger since the network is decentralized. A person attempting to alter the records will have their copy differ from that of the other node operators, preventing a consensus from being reached. If there is no consensus and the copies of the record do not agree, the node becomes inactive.