What is Ethereum (ETH)? A Plain-English Explainer
Ethereum is a blockchain for apps and smart contracts. Learn how ETH works, what it's used for, its history, risks, and how it compares to rivals.
In this article9 sections
Key points
- Ethereum is a blockchain network that runs small programs called smart contracts, enabling apps without a central operator.
- ETH is the network's native token, used to pay transaction fees and to secure the network through staking.
- Ethereum's main trade-offs are complexity, congestion-driven fees, and reliance on layer-2 networks for cheap transactions.
What Ethereum Is
Ethereum is a public blockchain network that can run small programs called smart contracts. Instead of only recording payments, it lets developers build applications that live on the network itself. Those applications can move money, track ownership, or enforce rules automatically. The network’s native token is called ether, or ETH.
Think of Ethereum as a shared computer that no single company controls. Thousands of independent computers, called nodes, keep a copy of the same record and agree on what happened. That record is the blockchain: a growing list of transactions and contract actions.
How It Works in Plain Language
A blockchain is a ledger that many computers maintain together. On Ethereum, anyone can submit a transaction, such as sending ETH or calling a smart contract. The transaction is broadcast to the network, checked by nodes, and then included in a block.
Validators, not miners, now produce blocks. To become a validator, a participant locks up at least 32 ETH as a deposit (since the 2025 Pectra upgrade, one validator can hold up to 2,048 ETH). Our staking guide covers rewards and penalties. The network randomly selects validators to propose blocks and to attest that other blocks are valid. Honest validators earn rewards; dishonest or offline ones can lose part of their deposit. This system is called proof of stake.
Smart contracts are programs stored on the blockchain. They run exactly as written when someone sends them a transaction. Once deployed, they generally cannot be changed, though developers can design upgradeable contracts. Because every node runs the same code, the result is the same for everyone.
Ethereum also has a virtual machine, the EVM, which is the standard environment for running these contracts. Most other blockchains either copy the EVM or offer a way to use it, which makes it easier for developers to move code between networks.
What ETH Is Used For
ETH has several jobs on the network:
- Paying fees: Every transaction and contract call costs a fee, paid in ETH. Fees compensate validators and help prevent spam.
- Securing the network: Validators stake ETH as collateral. The more ETH staked, the more expensive it becomes to attack the chain.
- Acting as money in apps: ETH is widely used as a form of collateral, a trading pair, and a unit of account in decentralized finance (DeFi) applications.
- Paying for digital goods: ETH is commonly used to buy NFTs and other on-chain assets.
ETH is not required to use every application. Some apps accept other tokens or stablecoins. But ETH is the asset that keeps the base layer running.
Notable History
Ethereum was proposed in 2013 by Vitalik Buterin in a white paper and launched on 30 July 2015. Its early years included a major test of its governance: after a 2016 hack drained funds from a project called The DAO, the community chose to rewrite the chain to return the funds. That decision split the network, creating Ethereum and Ethereum Classic.
In 2022, Ethereum changed how it secures the network. The upgrade, known as the Merge, moved the chain from proof of work to proof of stake. This cut the network’s electricity use by more than 99.98%, according to ethereum.org, and changed how new blocks are produced.
Ethereum has since focused on scaling through layer-2 networks. These are separate systems that process transactions more cheaply and then post compressed data back to Ethereum for security. There are 122,215,669 ETH in circulation, and ETH makes up 10.2% of the total crypto market value.
Ethereum upgrades that changed how it works
Ethereum changes through scheduled network upgrades. These are the ones a user or holder is most likely to notice, with mainnet dates from the ethereum.org upgrade history.
| Upgrade | Date | What changed |
|---|---|---|
| Frontier | 30 July 2015 | The network goes live |
| DAO fork | 20 July 2016 | Funds taken in The DAO hack are returned; the old chain continues as Ethereum Classic |
| London (EIP-1559) | 5 August 2021 | Fees split into a burned base fee and a tip (see gas fees) |
| The Merge (Paris) | 15 September 2022 | Proof of work replaced by proof of stake |
| Shapella | 12 April 2023 | Stakers can withdraw ETH for the first time |
| Dencun | 13 March 2024 | “Blobs” (EIP-4844) give layer-2 networks a cheaper place to post data |
| Pectra | 7 May 2025 | One validator can hold up to 2,048 ETH; ordinary accounts can use smart-account features (EIP-7702); more blob space |
| Fusaka | 3 December 2025 | PeerDAS lets nodes check blob data by sampling; default block gas limit raised to 60 million |
At 14 Nov 2026, 00:20 UTC, the Ethereum base fee was 0.08 gwei, so a simple ETH transfer cost under $0.01 and a typical token swap $0.03. Current figures for every transaction type are on our network fees page.
Main Risks and Criticisms
The most common concerns:
- Complexity: The network is harder to understand and use than simpler payment chains. Mistakes with private keys or contracts can be permanent.
- Fees and congestion: When demand is high, base-layer fees can spike. Layer-2 networks help, but they add their own steps and risks.
- Centralization pressures: A large share of staked ETH is held by a few providers, and some layer-2 systems rely on a small number of sequencers. This can create points of failure or influence.
- Smart contract bugs: Code can have flaws. Hacks and exploits have led to large losses over the years.
- Regulatory uncertainty: Rules for tokens, staking, and DeFi differ by country and continue to change.
- Competition: Other blockchains offer lower fees or different trade-offs, and some developers choose them instead.
How It Compares With Alternatives
Ethereum is often compared with Bitcoin and with newer smart-contract platforms.
| Network | Main focus | Key difference from Ethereum |
|---|---|---|
| Bitcoin | Digital money and settlement | Simpler scripting; no general smart contracts at Ethereum’s scale |
| Solana | High-speed apps | Different design; aims for low fees on a single fast chain |
| Cardano | Smart contracts with formal methods | Different programming model and development history |
| BNB Chain | EVM-compatible apps | Smaller validator set; closely tied to one exchange ecosystem |
Ethereum’s biggest advantage is its size and track record. It has the most developers, the most deployed contracts, and the deepest liquidity in DeFi. Its biggest disadvantage is that it is not the cheapest or fastest base layer. That is why its roadmap leans on layer-2 networks to handle everyday transactions while Ethereum itself serves as a secure settlement layer.
What to Watch
Ethereum’s future depends on several things: whether layer-2 networks become easy and cheap enough for mainstream use, whether staking becomes more decentralized, and how regulators treat tokens and DeFi. The next named upgrade, Glamsterdam, is listed by ethereum.org without a mainnet date yet.
Live: how much 1 Ethereum is worth today, with its market cap, supply and a USD converter.
Disclaimer: This article is for information only and is not investment, financial or trading advice. Cryptocurrency prices are highly volatile. Always do your own research.
