Apache Reference: mod_dir, DirectoryIndex

DirectoryIndex

List of Directory Index Files
Syntax: DirectoryIndex filename [filename ...]
Example: DirectoryIndex index.html welcome.html
Since: Apache 1.0

This directive sets the list of resources for which to search when the client requests an index of a directory by specifying a slash (``C'') at the end of the a URL. The filename is the (%-encoded) URL of a document on the server relative to the requested directory. It usually contains the name of a file in the directory. If several URLs are given, the server will return the first one that it finds. If none of the resources exists and the Indexes option is set, the server will generate its own listing of the directory.