The Hierarchy of a Domain Name
The Role of the Prefix
How Subdomains Work at the DNS Level
A Records and IP Mapping
CNAME Records and Aliasing
Practical Use Cases for Subdomains
- Development and Staging: Developers use subdomains like test.site.com to build and debug new features before they go live on the main site.
- Mobile Optimization: Before responsive design became standard, many sites used an ‘m.’ subdomain to serve mobile-specific versions of their pages.
- E-commerce: Many brands keep their store on a subdomain like shop.site.com to separate the heavy processing of transactions from their informational content.
- Geographic Targeting: International companies often use subdomains like uk.site.com or fr.site.com to provide localized content for different regions.
- Customer Support: Dedicated portals for documentation and tickets are frequently hosted on subdomains to keep the main site’s navigation clean.