What is a Top-Level, Second-Level, and Third-Level Domain

Every day we surf the vast internet, visiting thousands of different websites. But have you ever wondered how we get to the right resource? The answer is quite simple – through an address called a domain. A domain is a unique website name that allows us to quickly find the information we need. But what does the term "domain" really mean, and what levels does it have? Let’s break it down together.

Top-Level Domain

A top-level domain (TLD) is the highest part of the domain name hierarchy on the Internet. It is located on the far right of a domain name, right after the last dot. Examples of top-level domains include:

1. Generic Top-Level Domains (gTLDs): .net, .com, .org, .info.
2. Country-Code Top-Level Domains (ccTLDs): .ua (Ukraine), .us (USA), .de (Germany), .jp (Japan).
3. Sponsored Top-Level Domains (sTLDs): .edu (educational institutions), .gov (government organizations), .mil (military organizations).

Second-Level Domain

A second-level domain (SLD) is the part of a domain name on the Internet that is directly before the top-level domain and is used to identify a specific website, organization, or company. In the domain name structure, the second-level domain is located to the left of the last dot in the address.

For example, in the address example.com, .com is the top-level domain, and the example is the second-level domain. Examples of second-level domains include qhost, google, wikipedia.

The second-level domain is registered by a user or organization through accredited domain registrars and is unique within the chosen top-level domain.

Features

• Each second-level domain is unique within its TLD;
• It serves as the main identifier in a website's address;
• It often corresponds to a company's name, brand, or project.

Third-Level Domain

A third-level domain (also known as a subdomain) is the part of a domain name on the Internet that is located directly before the second-level domain. It is used for more detailed organization of the website structure and is often called a subdomain. In a website address, the third-level domain is located to the left of the second dot.

Domain Name Structure

1. Top-Level Domain (TLD): .com, .ua, .org.
2. Second-Level Domain: example, google, qhost.
3. Third-Level Domain (Subdomain): www, blog, shop.

For example, in the address blog.example.com, .com is the top-level domain, example is the second-level domain, and the blog is the third-level domain.

Features

• A third-level domain allows the creation of subdomains for various sections or services within the main website. For example:
  • shop.example.com — for an online store;
  • forum.example.com — for a forum;
  • support.example.com — for customer support.
• Owners of second-level domains can independently create and manage third-level domains without additional costs or the need for registration with domain registrars.
• Subdomains help organize content and separate different functional parts of a website, improving navigation and user experience.

SEO and Marketing

• Search Engine Optimization (SEO): Subdomains are treated by search engines as separate websites, so the content on them is indexed separately.
• Branding: Using subdomains allows businesses to highlight different business lines or projects under the main domain.

Technical Aspects

• DNS Settings: To create a third-level domain, you need to configure the appropriate records in the Domain Name System (DNS).
• SSL Certificates: When using HTTPS for subdomains, a separate SSL certificate may be required, or a wildcard certificate can be used to cover all subdomains.

FAQ

What is a domain zone?

A domain zone is the last part of a domain name that is separated by a dot from the rest. For example, in the address example.com, the zone is ".com". It indicates the type of organization or geographical location of the resource.

Can the domain level be changed after registration?

Changing the domain level after registration is generally not possible. This is due to the structure of the domain system, which is designed to ensure the uniqueness of each domain. However, there are ways to redirect or create aliases for existing domains.

What is a domain?

A domain is a unique name assigned to a website on the Internet. It’s like a postal address for your website, where users can find it.