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

Results fordjango.tworksystem.org

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2020-07-07T09:13:40.793	2020-07-07T08:13:40	2020-10-05T08:13:40	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-07-07T09:13:40.554	2020-07-07T08:13:40	2020-10-05T08:13:40	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-05-26T07:32:58.887	2020-05-26T06:32:58	2020-08-24T06:32:58	tworksystem.org	*.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-05-26T07:32:58.703	2020-05-26T06:32:58	2020-08-24T06:32:58	tworksystem.org	*.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-05-08T09:13:45.466	2020-05-08T08:13:45	2020-08-06T08:13:45	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-05-08T09:13:45.285	2020-05-08T08:13:45	2020-08-06T08:13:45	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-03-09T09:38:07.061	2020-03-09T08:38:06	2020-06-07T08:38:06	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-03-09T09:38:06.764	2020-03-09T08:38:06	2020-06-07T08:38:06	django.tworksystem.org	django.tworksystem.org	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3