InfrastructureLetter: B
What is Blockchain?
Definitive Definition
A blockchain is a distributed, immutable digital ledger of cryptographically linked blocks of data shared across a peer-to-peer network of computer nodes. Each block contains a cryptographic hash of the previous block, a timestamp, and verified transaction records, preventing retrospective alteration.
In-Depth Architectural & Economic Analysis
Blockchains provide transparent, tamper-proof record-keeping without relying on a central server or custodian. When a new batch of transactions is validated by network participants according to consensus rules, it is sealed into a block and permanently appended to the sequential chain.
Core Characteristics & Mechanism
- Distributed ledger replicated identically across all participating full nodes.
- Cryptographic hash pointers linking every block sequentially to genesis.
- Append-only architecture making historic transaction records immutable.
- Decentralized consensus mechanism ensuring state agreement.
Practical Application Scenario:
The Bitcoin blockchain has maintained uninterrupted, tamper-proof state consensus since Genesis Block 0 was mined on January 3, 2009.
Related Glossary Entries in Infrastructure
Gas Fee
A gas fee is the transaction fee paid by a crypto user to network validators or miners to compensate them for the computational power required to process, validate, and execute transactions or smart contracts on a blockchain network like Ethereum.
Layer 2 (L2)
A Layer 2 (L2) is a secondary protocol built on top of a base Layer 1 blockchain (such as Ethereum) designed to significantly increase transaction throughput and lower fees by processing transactions off-chain and settling compressed cryptographic proofs back to Layer 1.
Node (Full Node)
A full node is a computer connected to a blockchain network that downloads, stores, and independently validates every block and transaction against the consensus protocol rules, maintaining a complete, real-time copy of the distributed ledger.