Definition
A record-keeping system that tracks all transactions. In blockchain, the ledger is distributed — thousands of computers hold identical copies — making it tamper-resistant and transparent.
Why It Matters
Understanding the ledger concept explains why blockchain transactions are permanent and public. It's the fundamental data structure underlying all cryptocurrencies.
Example
The Bitcoin ledger records every transaction since January 2009. You can look up any transaction ever made on Bitcoin using a block explorer.
Related Terms
Blockchain
Block Explorer
Node
Decentralization