Ledger

Key points

• A ledger is the record where financial transactions are noted and kept over time, whether on paper, in a banking system, or on a blockchain.
• In crypto, the ledger is distributed: many identical copies are kept by different participants, without a single central custodian.
• This distribution, combined with cryptography, is what makes the history public, verifiable, and resistant to silent alteration.

What is a ledger?

A ledger is the accounting concept of a record where entries describing movements of value come in and out. In the traditional system, each bank keeps its own ledger and is responsible for its accuracy. In crypto, this role is fulfilled by the blockchain, which functions as a ledger shared across the entire network.

How it works

In a distributed ledger, each participant running a node keeps a complete copy of the history. When a new transaction is validated, it is added to that copy on all nodes, according to the network's consensus rules. Since there is no single authority that can rewrite the record, altering an old entry would require convincing the majority of the network, which is unfeasible on large chains.

Cryptography ties the records together: each block of transactions references the previous one, forming a chain in which any tampering becomes evident. This allows anyone to audit the history without needing to trust an intermediary, simply by verifying the data on their own.

What gets recorded is the movement between addresses, which are pseudonyms. The ledger shows what moved and to where, but does not directly reveal the identity behind each address.

Why it matters

A distributed, auditable ledger is the foundation of trust in crypto without a central intermediary. For a company settling amounts on-chain, it offers a record available at any time and verifiable end to end, which simplifies auditing and reconciliation compared to closed systems. This shared record also reduces disputes about what happened, since all parties consult the same source of truth, instead of reconciling separate systems that can diverge.

Risks and limitations

Maintaining many copies of the same record has a cost and limits processing capacity, which can raise fees during congestion. Full transparency also exposes the flow between addresses, a privacy consideration, even though identity is not directly linked to the records.