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

Results forwww.sailnote.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2019-05-20T08:44:22.896	2019-05-20T07:44:21	2019-08-18T07:44:21	www.avikmondal.co	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-05-20T08:44:21.697	2019-05-20T07:44:21	2019-08-18T07:44:21	www.avikmondal.co	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-03-22T17:15:05.776	2019-03-22T16:15:04	2019-06-20T16:15:04	eetkkinme.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-03-22T17:15:04.456	2019-03-22T16:15:04	2019-06-20T16:15:04	eetkkinme.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-01-21T17:43:56.432	2019-01-21T16:43:55	2019-04-21T16:43:55	www.sailnote.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-01-21T17:43:55.203	2019-01-21T16:43:55	2019-04-21T16:43:55	www.sailnote.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-01-21T14:51:27.276	2019-01-21T13:51:26	2019-04-21T13:51:26	www.sailnote.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-01-21T14:51:26.317	2019-01-21T13:51:26	2019-04-21T13:51:26	www.sailnote.com	www.sailnote.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3