1 Place downloaded and custom modules that extend your site
functionality beyond
Drupal core in this directory to ensure clean separation from core modules and
to facilitate safe, self-contained code updates. Contributed modules from the
Drupal community may be downloaded at http://drupal.org/project/modules.
It is safe to organize modules into subdirectories, such as "contrib" for
contributed modules, and "custom" for custom modules. Note that if you move a
module to a subdirectory after it has been enabled, you may need to clear the
Drupal cache so that it can be found.
In multisite configuration, modules found in this directory are available to
all sites. Alternatively, the sites/your_site_name/modules directory pattern may
be used to restrict modules to a specific site instance.
Refer to the "Developing for Drupal" section of the README.txt in the Drupal
root directory for further information on extending Drupal with custom modules.
2 Place downloaded and custom themes that modify your site's appearance in this
directory to ensure clean separation from Drupal core and to facilitate safe,
self-contained code updates. Contributed themes from the Drupal community may
be downloaded at http://drupal.org/project/themes.
It is safe to organize themes into subdirectories and is recommended to use
Drupal's sub-theme functionality to ensure easy maintenance and upgrades.
In multisite configuration, themes found in this directory are available to
all sites. Alternatively, the sites/your_site_name/themes directory pattern may
be used to restrict themes to a specific site instance.
Refer to the "Appearance" section of the README.txt in the Drupal root
directory for further information on theming.
3 This directory structure contains the settings and configuration files specific
to your site or sites and is an integral part of multisite configuration.
The sites/all/ subdirectory structure should be used to place your custom and
downloaded extensions including modules, themes, and third party libraries.
Downloaded installation profiles should be placed in the /profiles directory
in the Drupal root.
In multisite configuration, extensions found in the sites/all directory
structure are available to all sites. Alternatively, the sites/your_site_name/
subdirectory pattern may be used to restrict extensions to a specific
site instance.
See the respective README.txt files in sites/all/themes and sites/all/modules
for additional information about obtaining and organizing extensions.
See INSTALL.txt in the Drupal root for information about single-site
installation or multisite configuration.