Restarting Apache I get a warning

Hello everyone, when I restart Apache (httpd) it restarted fine however I get an error warning, see the following message;

Warning: DocumentRoot [/var/www/html/aastra/] does not exist
Warning: DocumentRoot [/var/www/html/restapps/] does not exist
httpd: Could not reliably determine the server’s fully qualified domain name, using localhost.localdomain for ServerName

Is this because I have not set a FQDN for my physical machine? ServerName is still set as default; localhost.localdomain. Also, what are directories/files aastra & restapps

I’m still figuring this all out so your thoughts are appreciated?
~Michael - AF7U