The Unified Payments Interface (UPI) is a real-time payment system developed by the National Payments Corporation of India (NPCI). It allows users to link multiple bank accounts to a single mobile application, enabling seamless money transfers and payments using smartphones. UPI facilitates instant transactions, making it convenient for both individuals and businesses. With UPI, users can send or receive money, pay bills, and make purchases online or in stores. The system operates 24/7 and supports various payment methods, including QR codes and mobile numbers. UPI has significantly transformed the digital payment landscape in India, promoting cashless transactions.