It can be anything! An apex, subdomain, or even a URL.

Results fordan.digitaldollarworld.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-06-22T02:17:43.951	2021-06-22T01:17:43	2021-09-20T01:17:42	dan.digitaldollarworld.com	dan.digitaldollarworld.com	C=US, O=Let's Encrypt, CN=R3
2021-06-22T02:17:43.361	2021-06-22T01:17:43	2021-09-20T01:17:42	dan.digitaldollarworld.com	dan.digitaldollarworld.com	C=US, O=Let's Encrypt, CN=R3
2021-03-26T05:23:02.063	2021-03-26T04:23:01	2021-06-24T04:23:01	dan.digitaldollarworld.com	dan.digitaldollarworld.com	C=US, O=Let's Encrypt, CN=R3
2021-03-26T05:23:01.749	2021-03-26T04:23:01	2021-06-24T04:23:01	dan.digitaldollarworld.com	dan.digitaldollarworld.com	C=US, O=Let's Encrypt, CN=R3