USDC is a U.S. dollar stablecoin first issued by Circle in September 2018 and designed to maintain a 1:1 peg to the U.S. dollar. USDC is backed by highly liquid U.S. dollar cash and cash-equivalent assets, with the majority of reserves held in the Circle Reserve Fund. In market infrastructure, USDC is used as a digital dollar for settlement, liquidity storage, and blockchain-based financial operations, with its positioning built around reserve transparency and integration into regulated financial infrastructure.