Subdomains

• Goals
  • Describe subdomains.
  • Skillfully use them when you create websites.

Subdomains (What)

A subdomain is an extension of a main domain name that allows Developers to organize different sections of their website under the same primary domain.

Examples:

• maps.google.com maps is subdomain of google.com.
• jokes.don-elger.com jokes is a subdomain of don-elger.com

The syntax is subdomain-name.main-domain-name.top-level-domain-nameNotice that the pattern is from specific to general.

Key Features of a Subdomain

1. Hierarchy: A subdomain comes before your main domain name. It’s separated by a period (.).

2. Independent Sections: Subdomains can function as separate sections of your site, allowing you to host different content, applications, or services.

3. Custom Use: You can set up multiple subdomains for various purposes, like:

   • blog.don-elger.com for a blog.
   • store.don-elger.com for an online store.
   • jokes.don-elger.com for your dad-joke app.

Why Use Subdomains?

• Organization: They help keep content organized, especially if your site offers diverse services.

• Different Applications: Subdomains can point to entirely separate servers or apps (e.g., a Flask app on Heroku).

• SEO Benefits: They can target specific audiences or regions without affecting your main site’s SEO.

• Custom Branding: Subdomains allow unique URLs that make services or sections stand out.

How Subdomains Work in DNS

A subdomain is configured in your domain’s DNS settings: * A CNAME record (or sometimes an A record) tells web browsers where to find the content for the subdomain. * For example, jokes.don-elger.com can point to a Heroku app using a CNAME.