Apex Domains, www, and Subdomains

This guide explains the difference between apex domains (also called root or naked domains), the www subdomain, and custom subdomains. Learn how A records, AAAA records, CNAME records, and ALIAS/ANAME records are used for each, why the apex domain cannot use a standard CNAME, how CNAME flattening works, and how to configure proper 301 redirects between www and non-www to consolidate SEO authority.