$ETH Ethereum (ETH) is a popular cryptocurrency known for its smart contract capabilities. It is a platform for decentralized applications (dApps) and other blockchain-based projects. Trading an ETH coin pair means you are buying or selling Ethereum for another cryptocurrency, such as Bitcoin (BTC) or Tether (USDT). The price of Ethereum fluctuates based on market supply and demand. Some people trade ETH coin pairs for speculation, while others view it as a long-term investment.