Ethereum (ETH)

Overview

Ethereum is a decentralized, open‑source, programmable blockchain that introduced smart contracts, enabling developers to build dApps, token systems, and on‑chain services. It is the second‑largest cryptocurrency and the core infrastructure behind today’s DeFi platforms, NFT ecosystems, and Layer‑2 scaling networks.

Key Features

• Speed: ~12–15 seconds per block; significantly faster on Layer‑2 rollups
• Fees: Variable gas fees; higher during network congestion, lower and more predictable on Layer‑2 networks
• Security: High — secured by a large, decentralized Proof‑of‑Stake validator set
• Consensus type: Proof of Stake (PoS)
• Smart contracts: Native — Ethereum pioneered programmable smart contracts
• Ecosystem size: Largest in Web3 — thousands of dApps, DeFi protocols, NFT platforms, and Layer‑2 networks

History & Background

Ethereum launched in 2015, created by Vitalik Buterin and co-founders (Gavin Wood, Joseph Lubin, Charles Hoskinson, and others). To provide a decentralized platform for running smart contracts and applications without downtime, fraud, or third‑party control — enabling trustless, programmable computation on a global blockchain network.

• 2015: Ethereum mainnet launches (Frontier), introducing the first programmable smart‑contract blockchain
• 2017: ICO boom brings mainstream attention to Ethereum‑based tokens and decentralized fundraising
• 2020: DeFi Summer drives explosive growth in decentralized finance on Ethereum
• 2021: EIP‑1559 (London upgrade) introduces fee‑burning, improving gas fee predictability and reducing ETH supply
• 2022: The Merge transitions Ethereum from Proof of Work to Proof of Stake, cutting energy usage by ~99.95%
• 2023: Shanghai/Capella upgrade enables validator withdrawals, completing Ethereum’s Proof‑of‑Stake transition
• 2023: Cancun/Deneb (EIP‑4844) introduces proto‑danksharding and blob transactions, dramatically reducing Layer‑2 fees
• 2024: Layer‑2 ecosystem expansion accelerates with Arbitrum, Optimism, Base, zkSync, and Starknet adoption
• 2025: Early danksharding preparations improve data availability and lay the foundation for full sharding
• 2026: Rollup‑centric roadmap advances with blob markets and enhanced Layer‑2‑first scaling

How It Works

Ethereum operates through the global, decentralized Ethereum Virtual Machine, which executes smart contracts that power dApps, tokens, DeFi protocols, and other on‑chain systems. These contracts run deterministically across thousands of nodes, ensuring trustless computation. The network uses Proof of Stake, where validators lock up ETH to propose, attest, and finalize blocks, earning rewards for honest behavior and facing slashing for malicious actions. Together, the EVM and PoS consensus secure Ethereum while Layer‑2 rollups extend its scalability with low‑cost, high‑throughput execution.

Consensus Mechanism

Ethereum uses Proof of Stake, where validators lock up 32 ETH to participate in securing the network. Validators are randomly selected to propose new blocks, while others attest to their validity, forming a decentralized consensus. Honest behavior earns staking rewards, while malicious or faulty actions can result in slashing, ensuring strong economic security without the energy‑intensive mining used in Proof of Work.

Tokenomics

• Total supply: No fixed maximum supply (deflationary pressure from EIP-1559 fee burning)
• Circulating supply: Approximately 120 million ETH
• Issuance schedule: New ETH issued to validators as staking rewards; issuance rate adjusts based on total ETH staked
• How new coins are created: Minted as validator rewards for proposing and attesting blocks under Proof of Stake
• Utility: Gas fees for transactions and smart contracts, staking collateral, collateral in DeFi protocols

Use Cases

Strengths

• Largest and most mature smart contract ecosystem
• Strong developer community with extensive tooling and documentation
• Energy-efficient Proof of Stake consensus mechanism
• Robust security track record supported by decentralization and real-world usage

Limitations

• Gas fees can spike significantly during periods of high network demand
• Scalability still depends heavily on external layer-2 solutions
• Complexity of the ecosystem can be a barrier for new developers and users

Supported Networks

• Ethereum Mainnet: The base layer-1 network; most secure but often has higher fees during peak demand.
• Arbitrum: Leading layer-2 rollup offering low fees, fast transactions, and a large DeFi ecosystem.
• Optimism: Optimistic rollup focused on scalability, low costs, and powering the Superchain vision.
• Base: Coinbase-backed layer-2 rollup known for low fees, high throughput, and rapid ecosystem growth.
• zkSync Era: ZK-rollup providing fast, low-cost transactions with zk-proof security.
• Starknet: High-performance ZK-rollup using STARK proofs for scalability and strong security guarantees.
• Linea: Consensys-built zk-rollup offering low fees and EVM-equivalent execution.
• Scroll: ZK-rollup closely aligned with Ethereum’s architecture, designed for native EVM compatibility.
• Polygon: Sidechain/layer-2 hybrid known for very low fees, high throughput, and broad dApp adoption.
• Gnosis Chain: Low-fee EVM-compatible sidechain used for payments, DAOs, and experimentation.
• Avalanche C-Chain: EVM-compatible chain offering fast finality and high throughput.
• BNB Chain: EVM-compatible network with large user adoption and low-cost transactions.
• Fantom: Fast, EVM-compatible network with low fees and rapid transaction finality.

How to Store It

ETH can be stored in software wallets such as MetaMask, hardware wallets like Ledger or Trezor, or held on regulated exchanges. Self‑custody wallets are recommended for long‑term holdings, enhanced security, and interacting with DeFi protocols. Learn more on our wallets guide.