All Drupal core modules, themes, scripts, libraries, includes, and text files have been moved to a "/core" subdirectory of the Drupal repository with the exception of these files/directories:
Placement of non-core modules and themes
- Following this change, contributed and custom modules can now be placed in the
modules/folder in the root of the Drupal installation, and contributed and custom themes can be placed in the similar
- This differs from Drupal 7 and earlier, where these folders were used for core modules and themes.
sites/all/themes/folders can also still be used, as can site-specific subdirectories.
core/themes/directories should never be used for contributed or custom modules.