What is a Domain Name?

A domain name is a name that resolves to an IP address, which is listed in a huge DNS database. You can think of this database as a phone book. The IP address is a phone number, and the domain name is the name that has the phone number.

Computers find each other by IP address, which looks like this: 123.123.123.123. This format is hard for a human to remember, so this is where a domain name comes into the picture. A human can remember a domain name, and so domain names are created to be more user friendly.

Parts of a Domain Name

There are several parts to a domain name. Let’s look at the domain name http://www.technicalconfusion.com

We will be starting with the far right, and read left.

.com – This is what’s called a “top level” domain name. It literally means commercial. There are others: .org for organization, .net for network, .ca for Canada. The list goes on.

technicalconfusion. – this is a first level domain name, which is off of the tree of the .com top level domain – to the left. “technicalconfusion.” resolves to your root folder, or user id given to you for your webhosting account.

www. – to the left of the top level and first level domain names, is a second level domain name, or, making it more complicated here, a subdomain. (Technically, everything other than the .com domain is nothing but a subdomain.)

www. technicalconfusion .com
Second LevelDomain name First LevelDomain Name Top LevelDomain Name
This is also what’s known as a subdomain:example.technicalconfusion.com Resolves to your userid folder on your server:/home/userid/public_html/ The server that is hosting your site

You can continue making lower level domain names, although it’s impractical for a normal user to do this.

To get a first level domain name, you must go to a domain name registrar for this. My personal favorite is GoDaddy.com, and even though I’ve used a number of registrars, they so far have been the best.

Recommended reading: Domain names and DNS

DNS and Bind