A Payment Gateway processes credit card and debit card payments, as well as other forms of electronic payments, primarily on behalf of e-commerce and brick-and-mortar merchants. The Payment Gateway is responsible for authenticating, standardizing and relaying transaction data between the merchants and the payment processors. The payment gateway responsibilities include securing payment data according to PCI DSS standards, securely sending transaction data to the payment processor, and storing the transaction and subsequent settlement, refund and other financial event data for later access by the merchant. Banks often own the payment gateways, but payment service providers (PSPs) like PayPal, Square or Stripe can also create their own Payment Gateway software.