USDC (USD Coin) is a stablecoin that is pegged 1:1 to the US dollar. Its stability is maintained through various mechanisms such as regular audits to ensure transparency and accountability, collateralization with USD held in reserves, and redemption options for users to exchange USDC for US dollars at a 1:1 ratio. These measures help to ensure that the value of USDC remains stable and closely tracks the value of the US dollar.