An API that allows browsers to act as an intermediary between the three key parties in a financial transaction: the merchant (e.g. an online web store), the buyer (e.g. the user buying from the online web store), and the Payment Method (e.g. credit card). Information necessary to process and confirm a transaction is passed between the Payment Method and the merchant via the browser with the buyer confirming and authorizing as necessary across the flow.
Docs: https://developers.google.com/web/fundamentals/primers/payment-request/ https://developers.google.com/web/updates/2016/07/payment-request?hl=en https://youtu.be/U0LkQijSeko https://developer.mozilla.org/en-US/docs/Web/API/Payment_Request_API
Samples: https://googlechrome.github.io/samples/paymentrequest/