Definition
Blockchain is a distributed database where information is stored in linked blocks. Each block contains transaction data and a reference to the previous block, forming an unbreakable chain.
How It Works
- Transaction — user sends cryptocurrency
- Verification — network validates the transaction
- Block — transactions are grouped into a block
- Hashing — block receives a unique code
- Addition — block is added to the chain
- Distribution — all network nodes update their copy
Key Properties
| Property | Description |
|---|---|
| Decentralization | No central server |
| Immutability | Records cannot be changed |
| Transparency | All transactions are public |
| Security | Cryptographic protection |
Types of Blockchains
- Public — open to everyone (Bitcoin, Ethereum)
- Private — access by invitation (corporate)
- Consortium — managed by a group of organizations
Blockchain Applications
- Cryptocurrencies — Bitcoin, Ethereum
- Finance — transfers, loans, insurance
- Logistics — goods tracking
- Documents — notary, voting
- Gaming and art — NFTs
Why Blockchain Matters
Blockchain solves the trust problem — participants can interact without intermediaries, relying on mathematics and cryptography instead of institutions.
