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

Results forem.tryforest.com

Resolver

Location

A

Name	TTL	Value
em.tryforest.com	60	108.138.64.31AWS CloudFront (GLOBAL) / Amazon.com, Inc.
em.tryforest.com	60	108.138.64.52AWS CloudFront (GLOBAL) / Amazon.com, Inc.
em.tryforest.com	60	108.138.64.111AWS CloudFront (GLOBAL) / Amazon.com, Inc.
em.tryforest.com	60	108.138.64.115AWS CloudFront (GLOBAL) / Amazon.com, Inc.