What are Domains?

Domain names are the human-readable Internet addresses of websites. Root domains, which are identified by their domain names, have extensions such as .com, .org, .net, etc. (Ex. http://www.example.com) Subdomains are a lower-level component of a root domain and precede the domain name. (Ex. http://subdomain.domain.com)

Top Tips

  • Word Separators
    Avoid hyphens. Hyphens detract from credibility and can act as a spam indicator.
  • Top-Level Domain (TLD)
    Top-level domains (like .com) are the extensions associated with domain names. For best ranking results, avoid uncommon top-level domains (TLDs). Like hyphens, TLDs such as .info, .cc, .ws, and .name are spam indicators.
  • Length
    Avoid domain names longer than 15 characters. Short domain names are easier to remember, easier to share, and have a smaller chance of resulting in typos.

What are Domains?

Root Domains

A root domain is the top level hierarchy of a domain. Root domains are purchased from registrars. The following are examples of root domains:

  • *.example.org
  • *.zdemy.com
  • *.blogspot.com


A subdomain is a “third level” domain name that is part of a larger, top-level domain. For example, “blog.example.com” and “english.example.com” are both subdomains of the “.example.com” root domain. Subdomains are free to create under any root domain that a webmaster controls.

The two most common subdomain choices are:

  • http://www.example.com (www is the subdomain)
  • http://example.com (has no subdomain)