1 

     2 This directory is reserved for core module files. Custom or contributed modules

     3 should be placed in their own subdirectory of the sites/all/modules directory.

     4 For multisite installations, they can also be placed in a subdirectory under

     5 /sites/{sitename}/modules/, where {sitename} is the name of your site (e.g.,

     6 www.example.com). This will allow you to more easily update Drupal core files.

     7 

     8 For more details, see: http://drupal.org/node/176043

     9