In Drupal, Single Directory Components (SDCs) represent a modern approach to organizing and building pages. This methodology involves structuring a website's pages using a single directory, containing all the necessary components like templates, stylesheets, JavaScript files, and other assets, associated with each page or component.
The concept of Single Directory Components is not native to Drupal but can be applied within Drupal projects, particularly those using decoupled architectures or modern front-end frameworks like React, Vue.js, or Angular.