Introduction
Blockchain is a distributed ledger technology (DLT) that stores data securely
across multiple nodes, making it tamper-proof, transparent, and
decentralized.
Key Idea: Once data is added to the blockchain, it cannot be altered without
consensus from the network.
1. Key Characteristics
Feature Description
Decentralization No central authority — data is shared among participants
Transparency Transactions visible to all participants
Immutability Once recorded, data cannot be modified
Security Uses cryptographic hashing and consensus mechanisms
Distributed Ledger Every node has a copy of the database
, 2. Structure of a Blockchain
A blockchain is made up of blocks linked together in a chain.
Each block contains:
1. Block Header:
Hash of previous block
Timestamp
Nonce (used for mining)
Merkle root (hash of all transactions)
2. Block Body: