How Blockchain Works
Distributed ledgers explained simply: blocks, chains, consensus and immutability.
Ledgers and Blocks
A blockchain is essentially a "ledger" recording every transaction. Transactions are bundled into "blocks," and each block links to the previous one via a cryptographic fingerprint (hash), forming a "chain." Once written, data is extremely hard to alter — changing any block breaks the fingerprints of all following blocks.
Decentralization and Consensus
There is no central server; the ledger is held in copies by nodes worldwide. To record new transactions, the network must agree via a "consensus mechanism" — Bitcoin uses Proof of Work (PoW), Ethereum uses Proof of Stake (PoS). This lets the system run reliably without trusting any single party.
Why It Matters
Blockchain's value lies in being transparent (anyone can inspect), immutable (history can't be forged), and permissionless (anyone can participate). This suits money, smart contracts, ownership proofs and any scenario needing "no trusted middleman."
