Understanding Domain Names

This is the fourth in our WordPress and Web Development series. Click here for the previous article and here for the next one .

Y ou might have heard someone say, “you should get yourself or your business a domain name.” A “domain name” gives you a personal identity on the web. Let’s try to understand this a bit deeper - who hands these names out, and how does buying a domain name relate to purchasing a website, or buying services from companies like Wordpress.com?

The Internet’s domain name system is one of the oldest components of the Internet. Each domain name is meant to identify a specific organization - someone who has authority or control over a group of machines that are connected to the Internet. The Wikipedia article on domain names goes into this in greater detail - the nub of it is that, right from the beginning, administrators on the Internet realized that it would be helpful to have a system to identify who was responsible for the computers that were connected to the Internet.

The system developed as a hierarchy - a part of the domain name would identify the primary purpose of the entity that owned the group of machines, another part would identify a specific region or entity, whatever was appropriate, and then the very last part would identify the function of those machines within that entity.

To make it less abstract, let’s consider the web address, www.whitehouse.gov. There are three parts to this address, separated by periods. The last part, “gov”, identifies the purpose - a website for government-related activities. Moving to the left from there, visually, we get to “whitehouse” - the executive branch of the government. Then, finally, we have “www” - the White House’s website, versus, say, the machines responsible for handling email which might be have the name “mail.whitehouse.gov”

Notice how we said “web address” above, to describe “www.whitehouse.gov”, rather than call it the “domain name.” Formally, the domain name is simply “whitehouse.gov” - that’s what is granted to the Executive Branch of the United States. Any functions within the White House can then be handled by additional “parts,” forming what are variously known as “sub-domains,” “fully qualified domain names (FQDNs)”, or “hostnames” - the White House for example might assign “pressreleases.whitehouse.gov” to feature media- and communications-related content.

Another instructive example is the domain name, amazon.com. “Www.amazon.com” goes to the main shopping website of Amazon, while “aws.amazon.com” goes to the cloud-computing services provided by Amazon, Inc. The “.com” suffix signifies the “primary purpose” - Amazon is a commercial entity, hence the “com,” meaning “COMmercial.” Amazon can then differentiate its various lines of business using sub-domains of “amazon.com”

The primary purpose portion of domain names has undergone many changes since the system was invented. One major change was when domain names were assigned to countries outside the United States. The very last part of a domain name could now identify not just the site’s primary purpose but its primary location within a sovereign boundary. Another change was that the “.com” ending became extremely popular, and became desirable for all types of entities - especially for individuals, who wanted to purchase the “.com” ending for their own names.

In the next section, we discuss how domain name purchases work.