Technical SEO
Domain
A domain is a human-readable address used to identify and access a website on the internet, consisting of a second-level domain name and a top-level domain (TLD) — for example, "google.com" where "google" is the second-level domain and ".com" is the TLD. Domains are registered through ICANN-accredited registrars like GoDaddy, Namecheap, or Google Domains.
Domain health and performance are monitored through WHOIS lookup services, Google Search Console (per property), and Ahrefs or SEMrush for domain-level backlink and organic traffic metrics. Domain authority scores (Moz DA, Ahrefs DR) provide proxy measures of a domain's ranking potential based on its backlink profile.
Authority Links
Related Terms
Technical SEO
Domain Age
Domain age represents how long it has been since the domain was first registered.
Measurement
Domain Authority
A third-party proprietary score (Moz DA, Ahrefs DR, SEMrush AS) on a 1–100 scale that estimates a domain's competitive ranking strength based on link profile quantity and quality — not a metric Google uses directly.
Technical SEO
Subdomain
Refers to a domain that is part of another domain.
Technical SEO
URL
Refers to unique web addresses that provide access to a resource on the Internet.