This document discusses headless Drupal architecture. Headless Drupal uses a decoupled architecture where the content management system (Drupal) is separated from the front-end interface. This allows Drupal to provide content via APIs to various front-end clients like mobile apps, websites built with JavaScript frameworks, and smart devices. Implementing headless Drupal involves setting up APIs in Drupal and using a front-end framework like Angular or Node.js to consume the API data and build interfaces. Popular sites using this architecture include The Tonight Show and Weather.com. Benefits include easier development and maintenance, scalability, and the ability to work with different frontend teams.