Apex Domains, www, and Subdomains

This guide explains the technical difference between apex domains (root or naked domains), the www subdomain, and custom subdomains. Topics covered: A records, AAAA records, CNAME records, and ALIAS/ANAME records and when to use each, why the apex domain cannot use a standard CNAME record, how CNAME flattening (also called ANAME) solves this, and how to configure proper 301 redirects between www and non-www to consolidate SEO authority onto a single canonical URL.