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dnsnomenclature

Domain name nomenclature

I want to refer to different parts of a domain, but do not know the names of the various parts. The RFC's on DNS don't seem to be explicit about this issue.

  • Given the domain: www.google.com

    "com" is called the generic Top level domain. What do we call "google" and "www"?

  • Given the domain: api.yahoo.co.uk

    "uk" is called the country code top level domain. What do we call "co", "yahoo", "api"?

  • Given the domain: sales.corporate.ge

    "ge" is called the sponsored top level domain (it is fictitious). What do we call "corporate" and "sales"?

Solution

  • First and third examples: google and corporate would be Second-Level Domains

    Second example: co is the Country Code Second-Level Domain (ccSLD)

    Below that, the terminology would be simply "subdomains" or occasionally "third-level domains".