ETH, or Ethereum, is a cryptocurrency and an open-source platform that enables the creation and execution of smart contracts and decentralized applications (DApps) on a blockchain network. It was proposed by Vitalik Buterin in 2013 and launched in 2015. Ethereum is more than just a cryptocurrency; it's a platform that allows developers to build decentralized applications on its blockchain.

Ether (ETH) is the native cryptocurrency of the Ethereum network and is used to pay for transaction fees and computational resources required to execute smart contracts and DApps on the platform. In addition to being a digital currency, ETH is also considered a digital asset and a form of investment.

In summary, ETH is the digital currency of Ethereum and is used to power operations within the network, including the execution of smart contracts and interaction with decentralized applications.