Blockchain

Ever wondered how bank transactions are kept safe?

Imagine you're sending money to a friend. You want to ensure that once you send the money, it can't be stolen or tampered with.

A blockchain is like a digital notebook that records every transaction. Each page is linked to the previous one, making it hard to change any entry without affecting the whole notebook.

Example

You send 100 to your friend, and this transaction is recorded on a new page linked to the previous page where you sent 50.

Remember this

The blockchain's linked pages make it impossible to alter past transactions without changing all subsequent ones.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

Related concepts

Smart contract

Smart contracts execute automatically on the blockchain

the blockchain trilemma says

The blockchain trilemma posits you can optimize only 2 of decentralization, security, and scalability

Proof of work

Miners solve puzzles to validate Bitcoin transactions

Peer-to-peer lending

Ever wondered how you can lend money without a bank?

a 51% attack is

A 51% attack involves controlling over half of the mining power to manipulate the blockchain

Proof of stake

Validators lock ETH as collateral to verify blocks

Educational content, not financial advice.

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