juniorBlockchain
What is a Genesis Block?
Updated Apr 28, 2026
Short answer
Blockchain is a decentralized, distributed ledger that records transactions across many computers. Unlike traditional databases, it is append-only and immutable.
Deep explanation
A blockchain is a chain of blocks where each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Databases are typically centralized and controlled by a single authority (CRUD operations), whereas Blockchains are decentralized (Append-only). This architecture ensures that data cannot be altered retroactively without the alteration of all subsequent blocks and the consensus of the network.
Real-world example
Bitcoin uses blockchain to track currency ownership without a central bank.
Common mistakes
- Thinking blockchain is just a 'slower database' or that it can only be used for cryptocurrencies.
Follow-up questions
- What happens if a hash changes?
- What is a double-spending problem?