Composer
Dependency manager for PHP.
#Development
Resources
Allow AJAX links to replace a specific selector
Create links that trigger ajax calls or displays content in a modal.
Remove jQuery dependency from the once feature
Switch from jquery once to once.
Drupal Includes
/core/includes directory.
Drupal\Component\Utility
Drupal utility classes.
Services and Dependency Injection Container
Drupal services and dependency injection documentation.
Entity API
Drupal Entity API documentation.
Hooks
Drupal hooks documentation
Basic structure of Drupal
Explains the Drupal codebase.
Core components are based on 3rd party libraries and other components.
Core subsystems are based on...
core_version_requirement
Specify supported core version in *.info.yml files.