$ETH Ethereum (ETH) is a decentralized, open-source blockchain platform with smart contract functionality. It is the second-largest cryptocurrency by market capitalization, after Bitcoin. ETH is used for a variety of purposes, including decentralized finance (DeFi), non-fungible tokens (NFTs), and decentralized applications (dApps).

Ethereum was first proposed by Vitalik Buterin in 2013 and went live in 2015. It has since become one of the most popular blockchain platforms, with a large and active community of developers and users.

In 2022, Ethereum underwent a major upgrade called "The Merge," which transitioned the network from a proof-of-work (PoW) consensus mechanism to a proof-of-stake (PoS) mechanism. This change is expected to make Ethereum more energy-efficient and scalable.