Normally you name your home page (the first page that you want visitors to see when they visit your web site) index.htm or index.html. When a browser visits your web site by typing in your domain name, i.e., www.yourdomain.com, the browser program will automatically search for a page titled index.htm or index.html (by default).
Alternately, if you create your main page in Perl or some other CGI language you could name it index.cgi.
If the browser does not find one, your visitor will not be able to access your web site without a specific page name to add to the domain URL.
There is also an extensive online manual available.
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