What is a Blockchain?
A blockchain is a distributed ledger — a list of records (blocks) linked by cryptography and replicated across thousands of computers simultaneously.
Linked Blocks
Each block stores data and the cryptographic hash of the previous block, creating an unbreakable chain back to the genesis block.
Decentralised
No single authority controls the chain. Thousands of independent nodes each hold a full copy — no single point of failure.
Immutable
Altering any block changes its hash, breaking every subsequent block. Rewriting history would require re-mining the entire chain.
Consensus
Nodes agree on the valid chain using Proof of Work or Proof of Stake — no trust in any single party required.
Smart Contracts
Self-executing programs stored on-chain. They run exactly as coded when conditions are met — no middlemen, no downtime.
Transparent
Anyone can audit the full history of public blockchains. Every transaction is permanently recorded and verifiable.
