You know how most video games have different levels? Well, so does DNS. While you aren’t powering up or getting skill bonuses while navigating the DNS hierarchy, each level of the domain name space plays an integral role in a query journey. In this resource, I’ll be covering the top-level domain (TLD) server.
What is a Domain?
First, let’s take a look at what a domain actually is. The average user doesn’t think “domain” when they enter a URL or search term into their browser—to most people, it’s simply a website or “Google.” A domain, however, isn’t so much a website as it is the location of a site. It’s what points to the numerical IP address where a website can be found. Just like a mail carrier needs your physical address to deliver a package, nameservers need to know the address of your website.
What is a DNS Server
A nameserver is a component of DNS that translates domain names into machine-readable IP addresses. These servers are also what allow devices and resources to connect with one another on the web. There are several different key server types that operate within the domain name system: recursive, root, TLD, and authoritative.
TLD Meaning
Now that we’ve covered some of the basics, let’s dive into what a top-level domain is and how it functions. In simple terms, a TLD refers to the letters after the dot in a domain name. These letters are often indicative of where a domain originated, what type of organization a website belongs to, or its purpose.
Top Level Domains in the DNS Process
During the DNS process, a recursive resolver receives a query and either answers it with information in its cache, or contacts a root server for an answer. The root server will then refer the recursive resolver to a TLD server. It’s a TLD server’s job to send the recursive resolver to the authoritative nameserver for the website in question. To finish the query journey, the authoritative nameserver provides the resolver with a final answer, so that it can direct the user to their intended destination.
Almost all queries end when a recursive server reaches an authoritative nameserver, but in rare instances where a final answer is not received, the process repeats.
TLD in DNS Structure
Here’s a visual of where TLD servers fit into the DNS hierarchical structure:
Tip: If you’d like to learn more about the DNS process, visit our What is DNS page or watch our DNS Explained video, which breaks it all down into easy-to-understand bytes!
TLD Example
Each website requires a unique name (and IP address) and must be associated with a top-level domain. There are many different TLDs, the most recognized of which being .com. Some of the other major top-level domains are .gov, .net, .edu, .mil, .biz, and .org. Two-letter country codes are also used for origination purposes (uk, ca, de, us, etc.).
Considering the sheer volume of sites online today—close to 2 billion— the selection of TLD names to choose from has grown significantly over the years. For instance, you can now have a .pizza, .info, or .travel website. In fact, the list of available TLD names is quite long.
Here’s a visual breakdown of what top-level domains looks like:
Did you know?: Seven top-level domains were introduced in 1984: .com, .org, .net, .int, .edu, .gov, and .mil. The .com extension (still the most widely used today) was originally meant for commercial purposes, but can now be used for any purpose.
Parts of a URL
Now, let’s take a look at the structure of a URL with a subdomain. For example purposes, I’ll use social.dnsmadeeasy.com. In this URL, the com is, of course, the TLD. The dnsmadeeasy portion of the web address is the second-level domain name, and social is a subdomain. This would be the same if it were dnsmadeeasy.com/social.
Subdomain Second-level Domain TLD
social. dnsmadeeasy .com.
Second-level Domain TLD Subdomain
dnsmadeeasy .com social
Did you know?: Some domain names were reserved by the Internet Assigned Numbers Authority (IANA) for documentation and illustration purposes? That’s why you see example.com, example.net, and example.org used in so many … you guessed it … examples.
Top Level Domain Wrap Up
The biggest takeaway here is that a TLD is the part of a domain name that comes after the dot (com, org, gov, uk, us). These extensions distinguish the purpose, geographical location, or type of organization a website belongs to. Each part of a domain name, including the TLD is needed for computers and other devices to load a website. Without the necessary data, you’d get nothing but an error message.
It’s also important to remember that TLD servers are just “messengers.” While they only tell resolvers which authoritative nameserver a specific domain is stored on, they are a crucial part of the DNS lookup process.
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