A blockchain is a special type of database where no single entity maintains control. This distributed structure enables trustless systems where participants can verify everything independently.
How Blockchains Work
Think of a blockchain as a digital ledger that's copied and shared across a network of computers. Every participant has the same copy, and changes must be agreed upon by the network.
Transactions are grouped into “blocks” which are then linked together in chronological order—forming a chain. Each block contains a reference to the previous block, making the history tamper-evident.
Key Properties
Decentralization
No central authority controls the blockchain. Instead, thousands of independent nodes around the world maintain copies and validate transactions. This removes single points of failure and prevents censorship.
Transparency
All transactions are publicly visible and auditable. Anyone can verify the complete transaction history from the very first block to the present.
Immutability
Once data is recorded on the blockchain, it cannot be altered or deleted. Each block is cryptographically linked to the previous one, so changing historical data would require re-computing every subsequent block—a practically impossible task.
Permissionless
Anyone can participate in the network. You don't need approval from any authority to send transactions, run a node, or build applications.
Consensus Mechanisms
For a decentralized network to function, participants need a way to agree on the state of the ledger. This is called consensus. Ethereum Classic uses proof-of-work, where miners compete to add blocks by solving computational puzzles.
The consensus mechanism ensures that even without a central authority, all participants can agree on which transactions are valid and in what order they occurred.
Beyond Digital Money
While Bitcoin introduced blockchain for digital currency, platforms like Ethereum Classic expand the concept with smart contracts—self-executing programs that run on the blockchain.
Smart contracts enable:
- DeFi: Financial services without intermediaries
- NFTs: Unique digital assets with provable ownership
- DAOs: Organizations governed by code instead of management
- dApps: Applications that run without central servers
Why Blockchain Matters
Blockchain technology enables digital systems that operate with the reliability of mathematics rather than the promises of institutions:
- Trust minimization: Verify, don't trust. Every claim is cryptographically provable.
- Censorship resistance: No authority can stop valid transactions
- Global accessibility: Anyone with internet access can participate
- 24/7 operation: Networks run continuously without downtime
Ethereum Classic's Role
Ethereum Classic is a proof-of-work blockchain that supports smart contracts. Running continuously since 2015, it provides:
- A secure foundation for decentralized applications
- Full EVM (Ethereum Virtual Machine) compatibility
- A fixed monetary policy with known supply
- Maximum decentralization through proof-of-work consensus
Next Steps
Ready to learn more? Explore our other articles on smart contracts, proof-of-work, and how to get started using Ethereum Classic.