What is a domain name?

A domain name or hostname is a name or label that identifies a resource like a web site. Domain names identify IP Addresses or Internet Protocol Addresses. The term “Domain Name” is the actual term used by internet professionals or web hosting companies while the term website name is more of a generic or slang term. See my previous post “What is a website name?” for details.

Domain names follow rules of the DNS or Domain Name System which is a hierarchical distributed naming system. In other words it’s a uniform naming and mapping system that relates letters, numbers and hyphens to a numerical designation. A domain name usually associates something a human can understand with that numeric designation.

I am about to drop a lot of acronyms so get out you letter blocks from grade school. Domain names are any combination of lowercase letters, upper case letters, numbers and hyphens. This is known as the LDH or Letters, Digits, Hyphen rule. Also, domain names may not start or end with a hyphen.

Domain names are organized or written in subordinate levels from right to left starting at the root domain which is nameless. The first level of domain names are called TLDs or Top Level Domains. There are several categories of TLDs.

There are gTLDs or Generic Top Level Domains like com, net, and org. There are ccTLDs or Country Code Top Level Domains like jp for Japan and ca for Canada. Also, there are sTLDs or Sponsored Top Level Domains like edu, gov and mil.

Subordinate to the TLDs are SLDs or Second Level Domains. These are written to the left of the TLDs. In the example yahoo.com ‘yahoo’ would be the SLD. Next of course would be third level domains and so on.

A good example of a four level domain would be the Delaware Department of Education’s website or www.doe.k12.de.us. The www is a naming convention that may or may not be used depending on the hosting provider.

Domain names can be obtained from a domain name registrars. Domain name registrars are companies accredited by the the organization responsible for overseeing the name and numbering system for the Internet ICANN. ICANN is an acronym for the Internet Corporation for Assigned Names and Numbers. You can search for and register domain names through the links at the top of this website if you are ready to move forward.

I hope this gives you a little better understanding of what a domain name is. Next post I’ll be offering some suggestions on how to name a website.

See you tomorrow.