This page provides a high-level overview of the standard integration sequence for processing card payments using the Direct API, incorporating EMV 3DS authentication. It covers all major stages of the transaction lifecycle—starting from order creation and card data submission, through to 3DS challenge handling and final authorization. This visual guide is designed to help developers quickly grasp the request and response flow, understand when to interact with external ACS (Access Control Server) endpoints, and recognize when key state transitions (e.g., STARTED, AWAITING_3DS, AUTHORISED, etc.) occur.