What Is an Domain Name? What is Domain Name System and Structure?

A Domain Name is a unique name registered to identify an individual computer, a group, or an organization on the Internet.

All domain names on the Internet are managed by the Domain Name System, which defines each domain name with a hierarchical structure of maximum 5 levels, for example: "algo.cs.ox.ac.uk". Reading to right to left, each level defines a realm of administrative autonomy, authority or control for subsequent levels.

• Top Level Domain - For example, "uk" is the top level domain for all domain names in United Kingdom.
• Category Domain - For example, "ac" is the category domain under "uk" for acdamic domain names in United Kingdom.
• Holder's Domain - For example, "ox" is the holder's domain under "ac.uk" for University of Oxford.
• Subdomain - For example, "cs" is a subdomain under "ox.ac.uk" for Department of Computer Science, University of Oxford.
• Computer Name - For example, "algo" is a computer name under "cs.ox.ac.uk" for a specific computer.

Other examples of domain names:

sports.yahoo.com
www.eecs.mit.edu
www.google.com
www.nic.ru
www.whitehouse.gov
swagger.io
analytics.dkv.global

⇒ DNS (Domain Name Server)

⇐ Domain Name Server/System

⇑ Domain Name Server/System

⇑⇑ Internet Connection - Frequently Asked Questions