Apache offers the ability to modify many global settings on a per-directory basis. This module provides access to that feature. To create an options file for a directory, simply enter the path and filename in the field and click Create Options File. By convention these files are called .htaccess, but that is a configurable option in Apache. This file also allows configuration of per-directory authentication among other access control features.
More information on options files can be found in the Apache docs under the Options directive.