Blockchain technology has become increasingly diverse in its applications over the past few years, with innovations like Ethereum's ecosystem, DeFi, GameFi, the metaverse, NFTs, and cross-chain solutions continually emerging. However, the most significant development in 2021 was the rise of public blockchains—a true era of explosive growth. This article will introduce you to public blockchains, their characteristics, and other foundational knowledge you should understand.
What Is Blockchain?
Before discussing public blockchains, we must first understand the basics of blockchain—what it is and how it operates.
The Origins of Blockchain
Blockchain technology was first introduced by Satoshi Nakamoto in 2008, with Bitcoin embodying the core concept of decentralization as a response to distrust in traditional financial systems.
Using blockchain, transactions can occur directly between parties without intermediaries (e.g., banks), with records being transparent, immutable, and publicly verifiable.
How Blockchain Works
Blockchain integrates multiple technologies—cryptography, mathematics, and algorithms—to create a decentralized, peer-to-peer network that operates without third-party oversight.
Bitcoin was the first digital currency to use blockchain technology, establishing a decentralized and transparent distributed ledger.
When a new transaction occurs on Bitcoin’s blockchain:
- The transaction is broadcast to nodes across the network.
- Nodes validate and record the transaction in a public ledger.
- Transactions are bundled into "blocks."
- Nodes compete to validate blocks using Proof-of-Work (PoW) consensus.
- The fastest validator adds the block to the chain, making it permanent.
- Nodes begin working on the next block, repeating the process.
This decentralized ledger system ensures security and transparency.
Common Blockchain Consensus Mechanisms
Most public blockchains today use Proof-of-Stake (PoS) mechanisms due to the energy inefficiency of PoW (used by Bitcoin and Ethereum).
- PoW: Relies on computational power (mining) to validate transactions—high energy consumption.
- PoS: Validators are chosen based on staked tokens, reducing energy waste and improving scalability.
Ethereum is transitioning from PoW to PoS in 2025 (ETH 2.0) to address these issues.
What Are Public Blockchains?
A public blockchain (Public Chain) is fully transparent—anyone can view transactions, participate in validation, and interact with the network using a wallet address.
Key Features
- Decentralization: No single entity controls the chain.
- Security: All nodes participate in validation, ensuring data integrity.
Use Cases
Since Ethereum's launch, public blockchains have expanded beyond simple ledgers to support:
- Smart contracts
- DeFi platforms
- NFTs
- DApps (decentralized applications)
However, Ethereum’s scaling issues (slow transactions, high fees) have led to competing blockchains like Solana, Avalanche, and BSC.
Public vs. Private vs. Consortium Blockchains
| Feature | Public Chain | Private Chain | Consortium Chain |
|--------------------|-------------------------|-------------------------|-------------------------|
| Access | Open to all | Restricted (permissioned) | Restricted (group-approved) |
| Decentralization | High | Low | Moderate |
| Speed | Slow | Fast | Fast |
| Examples | Bitcoin, Ethereum | Corporate databases | Hyperledger Fabric |
Top Public Blockchains to Invest In
| Blockchain | Key Features | Use Case |
|----------------|------------------------------------------|---------------------------|
| Bitcoin (BTC) | First blockchain, PoW consensus | Digital gold, payments |
| Ethereum (ETH) | Smart contracts, DeFi, NFTs | DApp development |
| Solana (SOL) | High-speed, low-cost transactions | Scalable applications |
| Avalanche (AVAX) | Subnets for custom blockchains | Enterprise solutions |
| Polygon (MATIC) | Ethereum scaling solution | Low-cost transactions |
FAQs
Q1: Are public blockchains secure?
Yes—their decentralized nature makes tampering nearly impossible.
Q2: Which blockchain is best for developers?
Ethereum for its ecosystem, Solana for speed, and Polygon for cost efficiency.
Q3: What’s the difference between PoW and PoS?
PoW uses mining (energy-heavy), while PoS uses staking (eco-friendly).
Q4: Can private blockchains interact with public ones?
Yes, via cross-chain bridges (e.g., Polygon ↔ Ethereum).
Q5: Is Ethereum 2.0 live?
The full transition to PoS is expected in 2025.
Final Thought: Public blockchains are foundational to Web3’s future—invest in ecosystems with strong use cases and active development.
Disclaimer: This content is for educational purposes only. Cryptocurrency investments carry risks; conduct your own research.