Unified Payment Interface or UPI is a joint initiative by National Payments Corporation of India’s (NPCI), Reserve Bank of India (RBI) and Indian Banks Association (IBA) to enable secure and extremely easy way to transfer money between bank accounts. It’s a payment mechanism which allows instant money transfer without the bank details. Instead of bank account number and IFSC code, a virtual payment address (VPA) is used here. To use this payment Mechanism one needs to download the bank specific app, such as Axis Pay, on their mobile phone and create a VPA which will be linked to their bank accounts.
A virtual payment address is an identifier that can be uniquely mapped to an individual account. It can be thought of like an email ID for your money that your bank uses to transfer money and make payments.