I elaborate a bit: public_html/drupal/core public_html/drupal/core/modules public_html/drupal/core/themes public_html/drupal/local public_html/drupal/local/modules public_html/drupal/local/themes public_html/drupal/local/sites public_html/drupal/local/sites/whatever/modules public_html/drupal/local/sites/whatever/themes