Ethereum

Ethereum is an open-source, decentralized blockchain platform that enables smart contracts and decentralized applications (DApps) to be built and run without downtime, fraud, control, or interference from third parties. Proposed by Vitalik Buterin in 2013 and launched in 2015, Ethereum introduced the concept of programmable money — transactions that can automatically execute based on predefined conditions. The native cryptocurrency, Ether (ETH), is used to pay for transaction fees (gas) and as collateral within the network. In September 2022, Ethereum completed 'The Merge,' transitioning from energy-intensive Proof of Work to Proof of Stake, reducing its energy consumption by over 99%. As of 2026, Ethereum is the dominant platform for decentralized finance (DeFi), hosting over $95 billion in total value locked across its ecosystem. Layer 2 scaling solutions (Arbitrum, Base, Optimism) now process approximately 20x the transaction volume of Ethereum mainnet, with fees under $0.02 per transaction. ETH is one of only two cryptocurrencies with spot ETFs approved in the US.