Ethereum is a public blockchain network designed to execute programmable applications. Its native asset, ether (ETH), pays for computation, secures proof-of-stake consensus and moves value across the network. Developers use Ethereum smart contracts to create tokens, decentralized finance protocols, stablecoins, games, identity tools and other applications whose state can be independently verified.

This guide follows Ethereum from a user’s wallet through transaction execution and finality. It explains accounts, the Ethereum Virtual Machine, gas, staking, tokens and Layer 2 networks, then separates protocol security from the wallet, contract and bridge risks that users still need to manage.

Ethereum explained in plain English

Ethereum is a shared computer whose state is replicated and checked by independent nodes. Anyone can submit a transaction, deploy compatible program code or verify the network’s rules. Instead of one company updating a private application database, Ethereum nodes execute the same valid transactions and agree on the resulting balances, contract storage and other state.

The network does not run software for free. Each transaction specifies a maximum amount of computational work and pays a fee in ETH. This prevents unlimited spam and allocates scarce block capacity. Proof-of-stake validators propose and attest to blocks, while node software verifies that every state transition follows the protocol.

Ethereum, ether and ETH

  • Ethereum is the blockchain network, protocol and broader software ecosystem.
  • Ether is the network’s native asset.
  • ETH is the common ticker and unit label used by wallets, exchanges and applications.

ETH is not a company share. Holding it does not create a contractual claim on the Ethereum Foundation or protocol revenue. It is used to pay gas, participate in staking, transfer value and serve as an asset or collateral in applications.

Why Ethereum was created

Bitcoin demonstrated that a decentralized network could maintain scarce digital value without a central ledger operator. Ethereum extended the idea toward a general programmable state machine. Instead of designing a separate blockchain for every application, developers could deploy smart contracts to a common network and let those contracts interact.

Vitalik Buterin proposed Ethereum in 2013, and a broader group of co-founders and contributors developed the early system. The public network launched in July 2015. Since then, Ethereum has changed through publicly discussed protocol upgrades rather than an automatic decision by one company.

Important moments in Ethereum history

  • 2015 — Frontier: the public network launched.
  • 2016 — The DAO incident: an application exploit led to a contentious chain fork and highlighted the difference between contract code and social governance.
  • 2020 — Beacon Chain: Ethereum began deploying its proof-of-stake consensus system.
  • 2021 — EIP-1559: transaction pricing added a protocol-determined base fee that is burned.
  • 2022 — The Merge: Ethereum replaced proof-of-work block production with proof of stake.
  • Later upgrades: protocol development increasingly supports rollup data, validator improvements and safer account functionality.

Historical milestones help explain today’s network, but wallet behavior and fee conditions should always be checked against current software and documentation.

How the Ethereum network is organized

Modern Ethereum separates responsibilities that older explanations often combine:

  • Execution layer: processes transactions, smart contracts and the Ethereum Virtual Machine state.
  • Consensus layer: coordinates proof-of-stake validators and agreement on blocks.
  • Validators: propose blocks and attest to the chain under staking rules.
  • Nodes: run execution and consensus clients and verify network data.
  • Wallets: manage user keys and prepare signed requests.
  • Applications: provide interfaces and smart-contract systems built on the network.

Using different independently maintained clients improves resilience. A software defect affecting one client is less likely to threaten the entire network when operators are distributed across implementations.

Ethereum accounts

Ethereum has two broad account types.

Externally owned accounts

An externally owned account, commonly called an EOA, is controlled by a private key. It can hold ETH and tokens, send transactions and call contracts. The account includes a nonce that helps order its transactions and prevents a signed transaction from being replayed indefinitely on the same chain.

Contract accounts

A contract account contains deployed bytecode and persistent storage. It does not spontaneously initiate a normal transaction; its code executes when called as part of a transaction or another contract interaction. The contract follows its code and current state, which may include administrator or upgrade permissions.

Both types use hexadecimal addresses. A familiar address format does not prove that an address belongs to the intended network, person or contract.

How an Ethereum transaction works

1. A wallet builds the request

The transaction identifies the destination, amount of ETH if any, encoded contract data, account nonce, chain identifier and fee limits. A basic ETH transfer contains little data, while a swap can call several contracts.

2. The user signs it

The wallet signs with the account’s private key. This authorizes the exact encoded request. It does not prove that the contract is safe or the visible website described the request honestly.

3. The transaction is broadcast

A wallet submits the signed transaction through an Ethereum node or remote procedure call provider. Valid pending transactions propagate and wait for possible block inclusion.

4. A validator proposes a block

A selected validator orders transactions into a candidate block. Other validators attest to their view of the chain, and nodes independently execute and verify the block.

5. The EVM changes state

The Ethereum Virtual Machine executes contract instructions. Successful execution can update balances, token ownership and contract storage or emit event logs. If execution reverts, state changes are rolled back, but computation already performed still consumes gas.

6. The block gains confirmation and finality

Wallets can display inclusion quickly, while applications may wait for additional confirmations or proof-of-stake finality. Inclusion and finality are related but not identical states. High-value services can apply their own deposit policies.

What is the Ethereum Virtual Machine?

The Ethereum Virtual Machine, or EVM, is the execution environment that defines how contract bytecode changes Ethereum state. Each validating node processes the same ordered inputs under the same EVM rules, producing a result that other nodes can verify.

The EVM is deliberately constrained. Instructions have gas costs, contracts cannot freely access the internet, and execution must be deterministic. These restrictions allow independent computers to agree on results.

Many other networks support EVM-compatible contracts and tools. Compatibility does not merge their balances or security. The same-looking address or contract interface can exist on separate chains with different validators and assets.

What is a smart contract?

A smart contract is program code and storage deployed at a blockchain address. Users and other contracts call its functions through transactions. A contract might manage a token, exchange pool, lending position, multisignature wallet or game.

“Smart” does not mean intelligent, legally enforceable or safe. The contract executes its programmed logic, including mistakes and dangerous permissions. Some contracts are immutable; others can be upgraded through proxy patterns or governance.

What contracts cannot know on their own

Ethereum contracts cannot independently determine a market price, election result, shipment status or weather event. Applications use oracles, signed messages or trusted operators to bring outside information onchain. The contract can verify the permitted input method, but the external data still has its own reliability assumptions.

What is a decentralized application?

A decentralized application, or dapp, usually combines several layers:

  • a website or mobile frontend;
  • a wallet connection;
  • smart contracts;
  • blockchain nodes or RPC providers;
  • offchain indexes, storage or oracles.

A dapp can use decentralized contracts while its domain, interface or data service remains centralized. If the frontend fails, contracts may still work through another interface. Conversely, a compromised frontend can request a malicious transaction even when the underlying protocol contracts are unchanged.

What ETH is used for

  • Gas: transaction senders pay network execution and block-capacity fees.
  • Staking: validators lock ETH as economic collateral.
  • Payments: users transfer ETH between accounts.
  • Collateral: DeFi protocols may accept ETH or tokenized representations of it.
  • Settlement: applications use ETH as a common native asset.
  • Incentives: validators receive protocol rewards and priority fees under current rules.

ETH used inside a lending protocol, bridge or liquid-staking system gains additional contract and counterparty dependencies beyond holding native ETH in a self-custody address.

How Ethereum gas works

Gas measures computational work. Each EVM operation has a defined gas cost. A transaction’s final fee depends on gas used multiplied by its effective price per gas.

Gas limit

The transaction gas limit is the maximum gas the sender allows the transaction to consume. Unused gas is not charged as if it had been consumed. A limit that is too low can cause execution to run out of gas and revert.

Base fee

Each block has a protocol-calculated base fee that responds to demand for block space. The base-fee portion paid by a transaction is burned rather than delivered to the validator.

Priority fee

The priority fee, sometimes called a tip, rewards block inclusion. Wallets typically estimate suitable fee settings from current network conditions.

Maximum fee

A sender can specify the maximum total price per gas they are willing to pay. The actual effective price can be lower. Wallet interfaces may simplify these values, but users should distinguish gas units from ETH or fiat cost.

Why Ethereum transactions fail

A transaction can fail because:

  • the contract deliberately reverts after a condition is not met;
  • the gas limit is insufficient;
  • slippage or deadline protection rejects a swap;
  • the account lacks a required token balance or allowance;
  • contract state changes before execution;
  • the called function or address is wrong.

A failed included transaction normally still pays for work nodes performed before the revert. Repeatedly resubmitting without reading the error can waste more ETH.

EIP-1559 and ETH burning

EIP-1559 introduced the elastic block gas target and base-fee mechanism. When blocks exceed the target, the base fee can rise; when demand falls, it can decline. Burning the base fee connects network use with ETH supply reduction.

This does not mean ETH supply always decreases. New ETH is also issued under proof-of-stake rules. Net supply change depends on issuance and the amount burned during a period. Avoid claims that Ethereum is permanently deflationary.

How Ethereum Proof of Stake works

Ethereum divides time into slots and epochs. In each slot, a validator is selected to propose a block, while other validators attest to blocks and the chain they consider valid. Consensus rules combine these messages to choose the chain and finalize checkpoints.

Validators place ETH at risk. Correct participation can earn rewards; being offline can miss rewards and incur smaller penalties, while provably conflicting or malicious actions can result in slashing. Proof of stake replaces mining work with staked collateral, protocol selection and validator messages.

Ethereum staking options

Solo staking

A solo validator supplies the protocol deposit, operates execution and consensus clients, protects signing keys and maintains uptime. This provides direct control but requires technical competence and reliable infrastructure.

Staking as a service

A provider can operate validator infrastructure for the owner. Control of withdrawal and signing credentials, fees, availability and legal terms vary. Verify exactly which keys the provider holds.

Pooled staking

Pooling lets users participate with less than the standalone validator deposit. The arrangement can add smart-contract, operator, governance and liquidity risks.

Custodial exchange staking

An exchange may handle deposits and validator operations while recording the customer’s position internally. This can simplify use but introduces platform solvency, withdrawal and account risks.

Liquid staking tokens

A liquid staking token represents a claim or protocol position related to staked ETH. It is not native ETH and can trade above or below an expected reference value. Its behavior depends on validator performance, contract design, withdrawal mechanics, liquidity and governance.

Using the token again as collateral creates layered risk: a validator issue, token depeg, lending liquidation or smart-contract failure can interact. A displayed staking yield should be evaluated after provider fees and these additional dependencies.

ETH supply and issuance

Ethereum does not use Bitcoin’s fixed 21-million maximum. Current supply changes through two opposing mechanisms: ETH issuance rewards proof-of-stake participation, while base fees are burned.

Protocol rules and staking participation influence issuance; network activity influences burning. Supply can expand or contract over a particular interval. Neither outcome guarantees market-price direction.

Tokens on Ethereum

Smart-contract standards make wallets and applications interoperable.

  • ERC-20: a common interface for fungible tokens.
  • ERC-721: an interface for individually identifiable non-fungible tokens.
  • ERC-1155: supports multiple fungible or non-fungible token types in one contract.

A standard defines compatible functions and events, not asset quality or legal rights. Anyone can deploy a token using a familiar name. Verify the contract address through authoritative sources.

Stablecoins on Ethereum

Stablecoins are widely used for payments, trading and DeFi settlement. Some represent issuer-managed claims backed by offchain reserves; others use onchain collateral and liquidation systems.

Ethereum confirms token-contract activity but cannot guarantee reserves, redemption, legal treatment or price stability. Issuers may retain freeze or blacklist functions. Decentralized designs can still depend on centralized collateral or oracles.

NFTs and digital ownership

An NFT contract records a unique token identifier and ownership state. The associated image or media can be stored separately, and owning the token does not automatically grant copyright or every commercial right.

Review the contract, metadata location, issuer terms and marketplace approvals. A wallet signature marketed as a free mint can instead authorize asset transfers.

DeFi on Ethereum

Ethereum contracts can coordinate exchanges, lending markets, liquidity pools, derivatives and tokenized positions. Their composability lets one protocol use another protocol’s assets or services, which expands functionality and transmits risk across dependencies.

Read What Is DeFi? for a detailed explanation of token approvals, automated market makers, liquidations, yield, oracles and bridges.

Ethereum Layer 1 and Layer 2

Ethereum mainnet is Layer 1. Layer 2 networks execute or bundle activity outside mainnet’s direct transaction path and publish data, state commitments or proofs back to Ethereum according to their design. This can lower user fees and increase capacity.

Using an L2 introduces its own contracts, sequencer behavior, bridge and withdrawal process. “Secured by Ethereum” does not mean every L2 has identical maturity, decentralization or escape mechanisms.

Optimistic rollups

Optimistic rollups generally treat submitted state as valid unless challenged during a defined process. Native withdrawals to Layer 1 can involve a delay, while third-party bridges may provide faster liquidity with additional assumptions.

Zero-knowledge rollups

ZK rollups submit validity proofs that allow Ethereum contracts to verify state transitions. Proof systems, data availability, upgrade controls and bridge contracts remain important parts of their security model.

Ethereum bridges

A bridge can lock an asset on one network and issue or release a corresponding representation on another. The destination asset depends on the bridge’s contracts, messages and operators or proof system.

Verify the official route, destination contract, withdrawal delay and network on both sides. Sending a token directly to an incompatible address or deposit route can make recovery difficult or impossible.

Ethereum versus Bitcoin

Characteristic Ethereum Bitcoin
Primary design focus General programmable applications and settlement. Peer-to-peer digital money and predictable monetary rules.
Native asset ETH. BTC.
Consensus Proof of stake. Proof of work.
Programming General-purpose EVM smart contracts. More constrained transaction scripting.
Supply model Dynamic issuance and fee burning. Maximum 21 million BTC.
Scaling emphasis Rollups and other Layer 2 systems. Lightning and other higher-layer systems.

Both networks are public and independently verifiable, but they make different design trade-offs. Read What Is Bitcoin? for Bitcoin mining, UTXOs, wallets, confirmations and supply.

Privacy on Ethereum

Ethereum is pseudonymous, not automatically anonymous. Public addresses expose balances and interaction history. Token approvals, NFT ownership and application activity can be linked over time.

Wallet connections also reveal addresses to websites and RPC providers. Centralized exchanges can associate withdrawals with verified identities. Avoid placing personal data directly onchain because public records can persist indefinitely.

Benefits of Ethereum

  • Programmability: developers can deploy general smart-contract applications.
  • Composability: contracts and standardized tokens can interact.
  • Open verification: users can inspect transactions, state and code.
  • Shared settlement: many applications use the same base network.
  • Open participation: compatible wallets and software can interact without a private integration.
  • Broad tooling: established standards support wallets, developers and infrastructure.

Ethereum risks and limitations

Smart-contract risk

An application contract can contain exploitable code or unsafe economic assumptions even while Ethereum itself operates correctly.

Wallet and approval risk

Malicious signatures and token approvals can authorize theft. A secure seed phrase does not help if the owner signs a dangerous request.

Gas volatility

High demand can make mainnet actions expensive. A user may be unable to exit or protect a position economically during congestion.

Bridge and Layer 2 risk

Bridges, upgrade keys, sequencers and proof systems add assumptions beyond holding native ETH on mainnet.

Validator and provider concentration

Large staking providers, client concentration and infrastructure dependencies can affect resilience and censorship resistance.

MEV and transaction ordering

Pending swaps and liquidations can attract automated strategies that influence transaction order and execution price.

Token and stablecoin risk

Ethereum hosts contracts; it does not endorse every issued asset. Tokens can be illiquid, upgradeable, frozen, misleading or worthless.

How to start using Ethereum more safely

  1. Select a reputable wallet and obtain it from a verified source.
  2. Back up the recovery phrase offline and never share it.
  3. Confirm whether you are using Ethereum mainnet or a specific Layer 2.
  4. Keep enough native ETH on that network for transaction fees.
  5. Test a new address or bridge route with a small amount.
  6. Compare the full destination address on a trusted display.
  7. Read decoded wallet requests, token approvals and gas estimates.
  8. Verify token and contract addresses through official documentation.
  9. Review completed activity in an appropriate block explorer.
  10. Revoke allowances that are no longer required.

Explore the site’s wallet resources and security guides before moving significant assets.

How to read an Ethereum block explorer

  • Transaction hash: the public identifier for the signed transaction.
  • Status: whether execution succeeded or failed.
  • Block: where the transaction was included.
  • From and to: sender and direct destination; contract calls may move assets elsewhere.
  • Value: native ETH sent directly with the call.
  • Token transfers: contract events indicating ERC-20 or NFT movements.
  • Gas used: computation consumed by execution.
  • Input data: the encoded function call and parameters.
  • Logs: events emitted by contracts during successful execution.

An explorer is an interface to public data, not a wallet-recovery service. Transaction lookup never requires a seed phrase or private key.

Common Ethereum scams

  • Fake airdrops: worthless tokens or NFTs direct users to a wallet-draining website.
  • Address poisoning: a similar-looking address is inserted into transaction history.
  • Malicious approvals: a contract receives permission to transfer valuable tokens.
  • Blind signatures: a user signs data they cannot interpret.
  • Impersonation: fake support accounts request a recovery phrase or remote access.
  • Recovery fraud: a service promises to reverse an onchain theft for an advance payment.
  • Counterfeit tokens: familiar names and logos hide an unrelated contract address.

Frequently asked questions

Who controls Ethereum?

No single person or company can unilaterally make every participant accept new protocol rules. Researchers and developers propose changes, client teams implement software, validators participate in consensus, node operators choose releases and users decide which network and assets to recognize.

Does ETH have a maximum supply?

Ethereum does not have Bitcoin’s fixed maximum. ETH is issued for proof-of-stake security, while base fees are burned. Net supply can increase or decrease over a period.

Why is ETH needed for gas?

ETH is the protocol’s native fee asset. Requiring payment prices computation and block capacity, compensates eligible validators through priority fees and helps limit spam.

Can an Ethereum transaction be cancelled?

A confirmed transaction cannot normally be reversed. A pending transaction from an EOA can sometimes be replaced using the same nonce and a competitive fee, but replacement is not guaranteed to arrive first.

Can staked ETH be lost?

Validators can lose rewards or incur penalties for downtime, and slashable behavior can destroy part of their stake. Pooled and custodial methods add provider, contract and liquidity risks.

Where is ETH stored?

Ethereum records account state on the blockchain. A wallet stores or protects keys used to authorize state changes; it does not hold ETH as a coin file.

Is a Layer 2 the same as Ethereum?

No. An L2 is a separate execution environment that settles information to Ethereum according to its design. It has distinct balances, contracts, fees and bridge procedures.

Is Ethereum anonymous?

No. Addresses do not automatically reveal legal names, but balances and transaction histories are public and can be connected to identities through other information.

Key takeaways

  • Ethereum is a public programmable blockchain; ETH is its native asset.
  • The EVM executes smart contracts, while gas prices computation and block capacity.
  • Proof-of-stake validators propose and attest to blocks using ETH as economic collateral.
  • ETH supply changes through validator issuance and base-fee burning.
  • Layer 2 networks reduce costs but add bridge, upgrade and sequencer assumptions.
  • Ethereum protocol security does not make every contract, token, wallet prompt or application safe.

Last reviewed: September 18, 2026. Network upgrades, contract interfaces, fees and staking rules can change. Verify current details before transferring ETH or interacting with an application. This guide is educational and does not constitute financial advice.

Sources and further reading