What Blockchain Is, In Plain Terms
Blockchain refers to a technology that distributes ledgers over a network of computers. Information recorded is in groups called blocks that are "chained" together in chronological order. Data entered into a blockchain cannot be altered or deleted, making blockchain useful for recording transactions and tracking assets.
Blockchain technology provides the backbone of cryptocurrency. Cryptocurrency using blockchain technology first started in 2009 with Bitcoin, introduced through the original Bitcoin whitepaper. Blockchain has evolved since its creation to adapt to areas such as finance, supply chain, health care, and elections.
How Blockchain Works
A blockchain has three parts: blocks, nodes, and miners.
Blocks
Blocks contain deal information. Each block consists of a list of deals, a timestamp, and a reference to the previous block. This reference, called a hash, chains the blocks together.
Nodes
Nodes are simply computers that store a copy of the blockchain. Computers that verify new transactions and propagate updates across the network are called nodes. Nodes are decentralized because they are not owned by any single party. That means that today's bitcoin price shows that the network has been running autonomously for more than fifteen years.
Miners
Miners are people who validate transactions ("checks deals") and mine new blocks to the chain ("adds blocks"). For this work miners are rewarded with cryptocurrency. Today's ethereum price is a testament to the growth of blockchain networks that run smart contracts.
How Agreement Is Reached
Blockchain networks have consensus mechanisms to agree on whether transactions are valid. Each blockchain network has its own consensus mechanism.
Proof of work (PoW) requires miners to complete complex mathematical equations to verify transactions. Bitcoin transaction verification utilizes this method. It consumes enormous amounts of processing power and electricity. Take a look at Litecoin price today for another cryptocurrency that runs on proof of work.
Proof of Stake (PoS) selects validators proportionally to their amount of cryptocurrency and how much they are willing to stake. Proof of stake blockchains require less energy than proof of work. The current Cardano price is listed for one of the largest proof of stake cryptocurrencies. Cardano is praised for implementing features after research and rigorous testing.
The Polkadot price today is another example of a proof of stake network. Polkadot allows interoperability between various blockchains.
Consensus Mechanisms Compared
| Attribute | Proof of Work | Proof of Stake |
|---|---|---|
| How validators are chosen | Compete to solve math puzzles | Selected by stake size |
| Energy use | High | Low |
| Hardware requirement | Specialized mining rigs | Standard server or PC |
| Example networks | Bitcoin, Litecoin | Cardano, Polkadot, Ethereum |
How Blockchain Tech Is Used
Blockchain tech has uses besides digital money.
Financial Services
Accelerated transactions with blockchain. Transactions with your bank may take days if you are sending money to another country. With blockchain transactions, you can complete them in minutes. Look at the Solana price today to see a blockchain capable of thousands of transactions per second.
Apps Without a Middle Man
Apps created by programmers that operate on a blockchain network rather than using centralized servers. Today's Avalanche price indicates a friendly platform for these applications with quick transaction speeds.
Layer Two Solutions
Layer 2 solutions are platforms that perform transactions off of the main blockchain while inheriting its security. Layer 2 solutions solve the scalability problem with base layer blockchains being unable to process high volumes of transactions. Polygon price today is one of the leading solutions to scale Ethereum.
Chatting Across Chains
A new blockchain network can communicate with another network. Today's Cosmos price is associated with interoperable blockchains.
Oracle Networks
Smart contracts require external data to function across most applications. Oracle networks safely feed that data to blockchains. The price of Chainlink today reflects the market's valuation of the leading oracle network.
DeFi
Decentralized finance refers to financial transactions that utilize blockchain technologies. DeFi services bypass traditional banks and intermediaries. Today's Aave price is one of the largest decentralized lending platforms.
Smart Contracts
Self-executing programs stored on a blockchain. When predefined conditions are met, they automatically execute themselves. Today's Tezos price is that of a blockchain with various mechanisms to ensure smart contract safety.
Good Things About Blockchain
Blockchain tech has things that make it different from normal databases:
- Transparent transactions. Every participant can inspect the full ledger.
- Tamper-resistant security. Cryptographic mechanisms prevent alteration of data after it is written.
- No single point of failure. The network is decentralized, so no individual node going offline breaks it.
- Immutable storage. Once data is verified and committed to a block, it cannot be altered.
Things to Think About
Blockchain technology comes with trade-offs worth weighing:
- Transaction speed. Certain networks are slower than traditional payment systems.
- Energy consumption. Proof of work blockchains remain a concern on this front.
- Usability. Blockchain applications can be inaccessible to non-technical users.
- Regulation. Local and national rules surrounding blockchain technology continue to develop.
Blockchain is a technology layer that supports far more than cryptocurrency alone. The same ledger pattern that records a Bitcoin transaction can record a supply chain checkpoint, a medical record signature, or an election ballot. The examples in this guide show where the technology already runs in production, and where real networks are competing on speed, cost, and security.
