It can be anything! An apex, subdomain, or even a URL.
Domain Name: www.standby.whois.aiDomain Status: No Object Found>>> Last update of WHOIS database: 2024-09-20T10:54:05.499Z <<<
Domain Name: www.standby.whois.ai
Domain Status: No Object Found
>>> Last update of WHOIS database: 2024-09-20T10:54:05.499Z <<<