Domain Name Systems (DNS) At Your Fingertips
June 13, 2017
When considering opening a website for the first time, making sense of how the Domain Name System works and the terminology associated with it can be daunting, especially when you are not IT savvy. This guide aims to simplifies the system and terms.
For starters, you need to understand what an IP address means.
Also called internet protocol address, an IP address is made up of four numbers, which are separated by a dot, each number ranging from one to three digits. For example, 22.214.171.124 is an IP address. Every computer has one. Online, an IP address is what one computer uses to locate and share information with another computer out of billions online. It’s kind of like a mailing address. You need it to send a letter to someone, and the recipient needs yours to send you one too.
What is a Domain?
Every website has both a domain name and one or more IP addresses. Domain names are simply a means of identifying those IP addresses. For instance, http://www.cnn.com/ is a domain name identifying CNN’s IP address. Thus, when you type the domain, it takes you to CNN’s website.
In URLs, domain names are also used to identify web pages. A good example is http://www.amazon.com/contact, which will typically point the user to the ‘contact’ page of Amazon’s website. What domain names do is simply provide us humans with an easier means of finding a website online. So instead of memorising IP numbers, we memorise domains, which are easier on the memory.
What’s a Domain Name System (DNS)
The DNS is an internet service, an electronic address system, designed to translate domain names into the various IP addresses they identify. Therefore, when a human types and executes a domain name like www.example.com, the DNS simply matches it with the corresponding IP address and then locates the website or server bearing that address.
The Domain Name System is made up of three levels: the Top-Level Domain (TLD), the Second-Level Domain (SLD), and the Third-Level Domain, also known as the subdomain.
Top-Level Domain (TLD)
The Top-level Domain is the DNS root zone, the highest level of domain names online. All domain names end with a top-level domain. There are three types of top-level domains:
- Generic Top-Level Domains (gTLDs). These are domain extensions like [dot]com, [dot]org, and [dot]net.
- Country code Top-Level Domain (ccTLDs). These are domain extensions associated with specific countries, and there are over 200 of them. Examples of ccTLDs are [dot]nz for New Zealand, [dot]es for Spain, and [dot]us for the United States.
- New Top-Level Domains (nTLDs). These are also considered gTLDs. The only difference is that they were introduced recently — typically between 2013 and 2016. They are easy to remember and make use of various generic words, including the names of important cities. Some examples include [dot]newyork, [dot]agent, and [dot]blog.
When you want to register a domain name, you get to choose from any of the 800 top-level domains.
Second-Level Domain (SLD)
Second-level domains are right below the top-level domain in the hierarchy. In a domain name, the second-level domain is the name before the TLD. For instance, in www.example.com, ‘example’ is the second-level domain. When registering a domain name, you get to create your own SLD. It can be your name, the name of your company, or any arrangement of letters or/and numbers.
Third Level Domain
Also referred to as subdomains, third-level domains are places before SLDs. They offer structure to a website and refer to the designation of servers. For instance, in www.example.com, ‘www’ is the third-level domain and typically refers to a web server. Mail.example.com, on the other hand, refers to a mail server, while ftp.example.com could refer to an ftp server.
How to Get a Domain Name
Now that you understand the terminology of the Domain Name System, the next thing you are probably wondering is how to get your own domain name. It’s easy: simply visit a domain registrar. A registrar is any institution that has a license from the Internet Corporation for Assigned Names and Numbers (ICANN) to sell domain services to the public. A great example is www.umbrellar.com, a domain registrar based in New Zealand.
But bear this in mind: registering a domain name only gives you ownership of the domain for a year—that is if you pay for a year’s registration. At the end of that time, if you don’t renew your registration, the domain name falls back into the pool of unregistered domain names and can be registered by someone else.
Learn more about how to choose and register a domain name here.