A domain name is effectively the address of your website, generally made up of the name of the site, plus a domain extension. Choosing the right domain name can have a huge impact on your site, building brand recognition and even driving traffic. That’s why it’s so important to understand the theory before you buy.

Domain vs URL

Domain names are often mixed up with URLs - but they’re not actually interchangeable terms in computer language. Instead, a domain name is part of the URL, which contains other useful information too. Here’s an example:

In this URL, www.fasthosts.co.uk is the domain name, while HTTPS is the protocol identifier. Bonus fact - the protocol identifier is essentially responsible for signalling how information is communicated between the host and a web browser.

How do domain names work?

Each domain name is linked to an associated IP address, which enables the browser to request information from the specific web servers where the site is hosted. Let’s look at what happens when you search for a website online:

  1. An internet user types a domain name into a web browser.
  2. The browser searches through the network of Domain Name System (DNS) servers for the relevant IP address.
  3. Once the DNS server with the right information is located, it sends the information about the IP address to the web browser.
  4. The browser then asks the domain’s hosting provider for data about the site - like the database and HTML code - which is stored on a web server.
  5. The hosting provider sends the web browser all the necessary information.
  6. Now the web browser can convert all these details into a usable webpage.

What’s the difference between a domain and web hosting?

A website requires both a domain name and web hosting to function. It can get a little confusing, so here’s a helpful analogy often used to explain the difference between the two: if your website is a house, then think of the domain name as the address, while web hosting is more like the land that the property is built on.

Domain name structures explained

Let's really break it down and get into the nitty-gritty of what makes up a domain name.

Domain extensions, AKA TLDs  

There are a few different components which make up the domain name structure. Domain names are read from right to left, so let’s start with the piece of text that comes after the dot at the end. This is known as the domain extension and these come in several different categories of their own:

  • gTLD - a generic top-level domain, for example .com
  • ccTLD - a country code top-level domain, like .fr (France)
  • sTLD - a sponsored top-level domain, like .gov

What other domain extensions are there?

While the most popular top-level domain by far is .com, followed by .org and .net, there are plenty of other options that are actually better suited for specific projects. For instance, did you know there are over 250 different country code top-level domains out there? Choosing a ccTLD as your domain extension can attract local customers and even help with your search rankings.

Similarly, you might choose a .shop domain extension for an ecommerce store, .biz for a business or .org if you’re running a non-profit organisation, charity or foundation – tell them what you’re all about before they even land on your site!

Second-level domains

As well as the top-level domain, there’s also the second-level domain (SLD), which is the portion of text that comes before the last dot in the domain name. This can look slightly different in every URL - let’s go back to the example we used earlier.

In our domain name – fasthosts.co.uk.co is the SLD, because this is the section directly before the final dot. But if we look at google.com instead, then google is the SLD, because the domain extension is different.


Subdomains aren’t in every domain name, but when they are, you’ll find them directly after the protocol identifier. They’re mostly used when a company wants to run a secondary domain (or child domain) under the umbrella of the main domain name - like when you want to create a mini-site under your main domain.

A good example that a lot of the top dogs use is help.domain, like Netflix has:

In this domain name, help is the subdomain, indicating that this is the Help section of their site, netflix is the SLD, and .com is the TLD.

Another example of a well-used subdomain is blog.domain. HubSpot is a good example:

In this case, you can see that that blog. is the subdomain - and it’s dedicated to the blog section HubSpot's site. There are plenty of other subdomains that could be handy for a company like this, like https://careers. or https://shop.

Why are domain names important?

A domain name is a unique identifier for your business, and can form the very foundation of your online presence. Still not sure if you need one? We've got plenty of ways a domain name can benefit not only your site but your brand:

  • Builds brand awareness. A simple domain name which includes the name of your brand or its core product/service will help to build brand recognition.
  • Drives traffic. An engaging domain name could increase user interest and even drive traffic directly to your site.
  • Provides custom email addresses. Investing in a unique domain name also gives you the opportunity to create custom email addresses, like bob.smith@fasthosts.co.uk (sorry Bob).
  • Increases credibility. Choosing a domain name and extension suited to your site makes your site appear more professional and trustworthy to users.
  • Helps with SEO. They may not be a significant ranking factor, but domain names can certainly contribute towards your performance on search engines, especially if you opt to include target keywords alongside your brand name.

Still not sure about choosing a domain name? We’re home to over 1.2 million domains, so if you have any questions we’ve got you covered – just get in touch! And if you’re looking for a reputable registrar with expert support available around the clock, we’ve got that too.