It is possible to name your default index page something other than index.html, index.cgi, index.php, etc., by using a directive in a special configuration file in your webspace. That file is called '.htaccess' (a dot followed by 'htaccess'). The directive needed is

DirectoryIndex foo.html
That will make the default page (i.e., the file name that will be requested if there's no filename in the URL, www.domain.com/) 'foo.html'. The change will affect the directory the .htaccess file is placed in and all sub-directories.