Topic Terms

What is Ethereum

Ethereum is a decentralized, programmable blockchain platform — the second-largest cryptocurrency by market cap — that allows developers to build smart contracts and decentralized applications (dApps), forming the foundation of DeFi and NFTs.

Ethereum (ticker: ETH) is the world's second-largest cryptocurrency by market capitalization and the leading platform for programmable blockchain applications. Proposed by developer Vitalik Buterin in 2013 and launched in 2015, Ethereum extended Bitcoin's original concept — a decentralized ledger for value transfer — into a programmable platform where developers can build and deploy smart contracts and decentralized applications (dApps).

Ether (ETH) is the native currency of the Ethereum network, used primarily to pay gas fees for executing operations on the network.

Why Ethereum Matters: The "World Computer"

Bitcoin was designed to do one thing very well: transfer value. Ethereum was designed as a general-purpose programmable blockchain — a platform where any logic can be encoded and executed in a trustless, decentralized environment.

This made Ethereum the foundation for:

  • DeFi (Decentralized Finance): Lending, borrowing, trading, yield generation — without banks
  • NFTs (Non-Fungible Tokens): Digital ownership and provenance for art, music, gaming items
  • DAOs (Decentralized Autonomous Organizations): Governance via token voting
  • Stablecoins: USDC, DAI, and other major stablecoins run on Ethereum
  • Token issuance: The ERC-20 standard (Ethereum's token standard) enabled the ICO boom of 2017–18 and powers thousands of tokens

ETH and Gas Fees

Every operation on Ethereum — sending tokens, interacting with a smart contract, minting an NFT — requires payment of a gas fee in ETH. Gas pricing fluctuates based on network congestion.

During peak usage (like popular NFT drops or DeFi market activity), gas can be extremely high — sometimes $100+ per transaction. During quiet periods, it can be cents. This gas fee model ensures that network resources are allocated to people who value them, while compensating validators for their work.

Layer 2 solutions like Arbitrum, Optimism, and Base process transactions off the main chain and settle batches on Ethereum — dramatically reducing gas costs. Learn more about how Layer 2 blockchains work and which networks are most widely used.

The Merge: Ethereum's Transition to Proof-of-Stake

Ethereum's most significant technical upgrade was The Merge in September 2022 — the transition from proof-of-work (energy-intensive mining) to proof-of-stake consensus.

Impact of The Merge:

  • Energy reduction: ~99.95% reduction in energy consumption — one of the largest corporate sustainability moves in tech history
  • Validator participation: Anyone with 32 ETH can become a validator (or use staking pools for smaller amounts) — see staking
  • Issuance reduction: Miner rewards were replaced with staker rewards; ETH issuance rate dropped ~90%
  • "Ultrasound money": Combined with EIP-1559's fee-burning mechanism, ETH became deflationary in high-usage periods

Ethereum vs. Bitcoin

Feature Bitcoin Ethereum
Primary purpose Store of value / digital money Programmable platform
Consensus Proof-of-Work Proof-of-Stake (since 2022)
Supply cap 21 million BTC (hard cap) No hard cap; deflationary pressure via burns
Smart contracts Limited (Bitcoin Script) Full Turing-complete EVM
Transaction speed ~7 TPS ~15–30 TPS (much more with L2)
Energy use High (PoW mining) Minimal (PoS)

Ethereum Ecosystem

Ethereum hosts a vast ecosystem:

  • Wallets: MetaMask (most popular), Coinbase Wallet, Rainbow
  • DEXs: Uniswap, Curve, Balancer
  • Lending: Aave, Compound
  • NFT marketplaces: OpenSea, Blur
  • Layer 2 networks: Arbitrum, Optimism, Base, zkSync

Ethereum's EVM (Ethereum Virtual Machine) architecture has become an industry standard — many competing blockchains (Avalanche, Polygon, BNB Chain) are "EVM-compatible," allowing Ethereum developers to deploy applications on other chains with minimal changes.

Despite competition from faster, cheaper alternatives (Solana, etc.), Ethereum's head start in developer tooling, liquidity, and security has maintained its position as the dominant platform for decentralized applications.