How Blockchain Works | GoAI Insights

How does blockchain function? Imagine a chain of digital safes, where each safe contains transaction records, a timestamp, and a unique identifier (hash). Each safe is locked with a cryptographic key derived from the previous safe’s data, forming a secure chain. If someone attempts to alter any past data, the entire sequence of safes would be disrupted, alerting the network and preventing tampering.

Blockchain security is reinforced by consensus mechanisms, which ensure that all participants follow the rules. The two most common mechanisms are:

Proof of Work (PoW): Used by Bitcoin, where miners compete to solve complex mathematical problems to validate transactions and add new blocks.
Proof of Stake (PoS): Used by Ethereum, where validators stake cryptocurrency to participate in securing the network.

Both methods protect against a 51% attack, where a single entity gains control of most of the network’s computing power or stake and manipulates transactions. This is a major security risk, particularly for smaller blockchain networks.

Additionally, blockchain relies on cryptographic techniques for security:

Public key: A unique address for transactions.
Private key: A secret key used to sign transactions and prove ownership.

For example, if Alice sends Bitcoin to Bob, she signs the transaction with her private key, and Bob can verify it using her public key.