What is Blockchain?

A blockchain is a distributed, decentralized digital ledger that records transactions across many computers. This technology ensures that records cannot be altered retroactively without changing all subsequent blocks.

Core Characteristics

**Decentralization**: No single entity controls the network

**Transparency**: All transactions are visible to participants

**Immutability**: Once recorded, data cannot be easily modified

**Security**: Cryptographic techniques protect the data

How It Works

A transaction is requested and broadcast to the network

Network nodes validate the transaction using algorithms

Verified transactions are combined into a block

The block is added to the existing chain

The transaction is complete and permanent

Real-World Applications

**Cryptocurrency**: Bitcoin, Ethereum, and other digital currencies

**Supply Chain**: Tracking products from origin to consumer

**Healthcare**: Secure patient record management

**Voting Systems**: Transparent and tamper-proof elections