$ETH Ethereum (ETH) is a decentralized blockchain platform that enables smart contracts and decentralized applications (dApps). Launched in 2015 by Vitalik Buterin, it introduced programmable transactions, unlike Bitcoin. Ether (ETH) is its native cryptocurrency, used for fees and computational services. Ethereum pioneered DeFi, NFTs, and Web3 innovations. In 2022, it transitioned from Proof-of-Work (PoW) to Proof-of-Stake (PoS) with "The Merge," reducing energy use by ~99.95%. Upgrades like sharding aim to improve scalability. Ethereum remains the leading smart contract platform, though rivals like Solana and Cardano compete for speed and cost efficiency. ETH is the second-largest crypto by market cap after Bitcoin.