Blockchain
Decentralized and secure system for continuous information recording.
Beginner-friendly explanation
Blockchain is like a big digital notebook everyone can read but no one can change alone. Each new piece of information is recorded on a "page" (a block) added to the notebook. Thanks to collective verification, it ensures that data is true and secure.
📌 Example: Bitcoin uses a blockchain to publicly and securely record all transactions.
Intermediate-level insight
Blockchain is a distributed database operating without a central authority. Each block contains information (transactions, contracts…) validated by a network of computers called nodes. It relies on consensus mechanisms like Proof of Work or Proof of Stake to ensure integrity.
📌 Example: Ethereum uses blockchain to automatically execute smart contracts without intermediaries.
Advanced perspective
Blockchain is an append-only data structure based on asymmetric cryptography and decentralized validation. Each block is linked to the previous one via a cryptographic hash, creating an immutable chain. It enables complex applications: decentralized finance, NFTs, supply chain tracking, with scalability (sharding, rollups) and security (51% attacks, MEV) challenges.
📌 Example: The Optimism protocol improves Ethereum's scalability by using secondary blockchains called rollups.
Blockchain & Technology
blockchain, database, decentralization, proof of work, proof of stake, security, distributed network, smart contracts, immutability