The website must have a domain name for it to appear on the web. Individuals and commercial organizations can buy domain name for their website from a domain registrar at a reasonable cost. This is a piece of string that helps identify the site.
For example, at www.microsoft.com, microsoft.com is the domain name. Addon Domain and Subdomain are two types of domain names. The domain addon allows the user to register a new domain name using the original hosting account. A subdomain is a subsection of a registered domain name.
What does a domain name consist of?
All domains are arranged hierarchically: they consist of parts (levels). Third-level domains are created on the basis of second-level domains, and second-level domains are created on the basis of first-level domains. Let’s take a closer look at the types of domains:
Domain of the second (third, fourth, etc.) level or subdomain – the left part of the domain up to the dot. In practice, this is any combination of characters that we come up with for the name of our future site (youtube.com, shop.reg.ru). As the ship is called, as they say, but that’s a completely different SEO story.
The first-level domain or domain zone is the right side of the domain after the dot. This part cannot be set by anyone other than ICANN. By registering a “domain”, we come up with a second-level domain and choose a zone. They can be geographic (.RU – Russia, .EU – EU countries, .AC – Ascension Island, etc.) or thematic (from old-timers like .COM. – commercial sphere, .BIZ – business sphere to new gTLD: . FLOWERS, .HEALTH, .CHILDREN, etc.).
Zero-level domain is a dot after the domain zone (reg.ru.), which is not displayed in the address bar and is omitted when entering the domain into the browser line.
In secondary domains, all other sites configures using the hosting account that useS to host the original or primary site. The user only has to pay for one hosting account and register domains under it without additional hosting costs. All files and content can manage using the main domain. This is a cost effective method when a user needs a collection of different sites under different names for their business.
A subdomain is the smaller part of a large domain. This allows you to send visitors to a different web address. The main advantage of using a subdomain is that it allows you to organize or divide your content into separate sections. If the site has a lot of content, it is possible to create subdomains. The subdomain separates the content from the main content and gives it a unique web address without registering a new domain name.
For example, suppose there is a website www.myshop.com. You can create subdomains under the registered domain name “myshop.com”, for example store.myshop.com, info.myshop.com, events.myshop.com, and so on.
Each of them has dedicated web addresses. These subdomains help organize your main content. They also help drive more visitors to your site. In addition, subdomains help create language versions of a website.
All in all
A domain name is a string that identifies an organization on the WWW. Addon and subdomain are two types of domains. The difference between an addon domain and a subdomain is that an addon domain is a domain. That add to the user’s hosting account that use to host its original domain, while a subdomain is the part directly link to the user’s original domain.
Source of information: hostens.com