Ethereum (ETH) is the second largest digital currency by market capitalization, and it is the native currency of the Ethereum network, which is a decentralized platform that allows the creation and operation of decentralized applications and smart contracts.

Ethereum is used to pay transaction fees on the network, known as "gas". It also plays a vital role in the operation of decentralized applications, incentivizing developers and participants in the network.

Since its launch in 2015, Ethereum has experienced tremendous growth and has become a cornerstone of the decentralized finance (DeFi) world and non-fungible tokens (NFTs). It continues to evolve with upgrades aimed at improving its scalability and efficiency.