Tether (USDT) is an Ethereum token that is pegged to the value of a U.S. dollar (also known as a stablecoin). Tether’s issuer claims that USDT is backed by bank reserves and loans which match or exceed the value of USDT in circulation. Important note: at this time, Coinbase only supports USDT on the Ethereum blockchain (ERC-20). Do not send USDT on any other blockchain to Coinbase.

Optimism is a network of chains called the Superchain, built on the open-source OP Stack. OP Mainnet was the first chain, with several others now operating on the OP Stack architecture, including Base (by Coinbase), Unichain (by Uniswap), Ink (by Kraken), and World Chain (by Worldcoin). The OP Stack serves as a framework for Ethereum Layer 2 chains and supports significant L2 activity. Every OP Chain in the Superchain contributes back to the Optimism Collective and all chains follow a standardized revenue-sharing model: the greater of 2.5% of total chain revenue or 15% of onchain profit (defined as fees minus L1 gas costs) is paid back to the Optimism. By aligning economic incentives across many chains, Optimism aims to transform Ethereum scaling into a sustainable flywheel by delivering fast, low-cost transactions while reinvesting in the future of the ecosystem. OP holders participate in governance to shape protocol upgrades, funding decisions, and more