What is a blockchain?

A blockchain is a shared record of transactions that lots of computers hold copies of at the same time. Think of it as a public spreadsheet that no single person owns — and that's very hard to cheat.

Why "block" and "chain"?

Transactions are bundled into blocks. Each new block is mathematically linked to the one before it, forming a chain. Because every block references the last, you can't quietly edit an old entry without breaking every block after it — which the rest of the network would instantly reject.

Who keeps it honest?

Thousands of independent computers ("nodes") each store the ledger and must agree before a new block is added. This agreement process (called consensus) is what removes the need for a bank or company to be the trusted middleman.

Why it matters for you

The blockchain is why crypto can be sent worldwide, 24/7, without a bank — and why balances are public and verifiable. It doesn't make any coin a good or safe investment; it's just the plumbing underneath.