What is the htaccess Options -Indexes for?

Question

I looked at the explanation in the apache.org site but it didn’t explained in a way I can understand. I found some info here .htaccess File Options -Indexes on Subdirectories bu

Answer 1

-Indexes supresses the possibilty of directly listing files in a directory where no DirectoryIndex is set.

Assume a httpd DirectoryIndex set to: DirectoryIndex index.html index.php.

If you have no file in your RootDirectory according to the DirectoryIndex httpd (in this example index.html and index.php) variable, your directory contents will be listed when +Indexes ist set. Your directory contents will never be displayed when -Indexes is set.