A blockchain is a shared digital ledger \u2014 a record of transactions \u2014 that is copied across thousands of computers and kept in sync without any central authority. It is the technology that lets crypto exist without a bank in the middle.<\/p>\n
Transactions are bundled into blocks<\/em>. Each new block includes a cryptographic fingerprint of the one before it, linking them into a chain. Change anything in an old block and its fingerprint changes, which breaks every block after it \u2014 so the history is effectively tamper-evident.<\/p>\n Instead of one company running the database, a network of independent computers (nodes) each holds a copy and agrees on new blocks through a consensus<\/em> mechanism \u2014 proof of work (mining) or proof of stake (staking) being the two most common. This is what makes a blockchain decentralised: no single party can quietly rewrite it.<\/p>\n Because the ledger is public and shared, anyone can verify balances and transactions for themselves. You do not have to trust an institution to tell you the truth; you can check the rules and the record directly. That transparency is the core idea \u2014 and the reason blockchains are slower and more expensive than a centralised database, since every node does the work.<\/p>\nWho keeps the record?<\/h2>\n
Why it matters<\/h2>\n