Ethereum is a decentralized blockchain network launched in 2015, designed to support smart contracts and decentralized applications (dApps). It uses Ether (ETH) as its native cryptocurrency, which is widely traded and utilized for transaction fees and network operations. Ethereum has played a pivotal role in the growth of decentralized finance (DeFi) and non-fungible tokens (NFTs), and its ongoing upgrades aim to improve scalability, security, and energy efficiency.