The Gemini dollar (GUSD) is an ERC20 stablecoin that allows holders to send and receive USD across the Ethereum network.
The Gemini dollar can be exchanged for other cryptocurrencies on other exchanges offering different trading pairs. Gemini Trust Company controls the creation or "minting" of all GUSD. Since it's backed by American Currency on a 1-to-1 exchange rate with the USD, the Gemini dollar can be redeemed at any point for 1 USD on Gemini.
You can read more about the Gemini dollar as the world’s first regulated stablecoin in our white paper here: https://gemini.com/wp-content/themes/gemini/assets/img/dollar/gemini-dollar-whitepaper.pdf