PCI, or Payment Card Industry, refers to a set of security standards designed to protect card information during and after a financial transaction. These standards are established by the Payment Card Industry Security Standards Council, which includes major credit card companies like Visa, MasterCard, American Express, Discover, and JCB. The main goal of PCI compliance is to ensure that all companies that accept, process, store, or transmit credit card information maintain a secure environment. This helps prevent data breaches and fraud, safeguarding both businesses and consumers from potential financial losses.