What does a second-level domain name mean?

In the online world, domain names are the key identifiers for accessing websites, and second-level domain names are an important part of them. It has unique meanings and functions, and is of great significance to the organization, management, and user access experience of websites. So do you know what a second-level domain name means?

The second-level domain name is a concept in the Internet domain name system.

1. Definition

- Domain names are hierarchical, from right to left, they are top-level domain names (TLD, Top-Level Domain), second-level domain names, third-level domain names, etc. The second-level domain name is the part on the left of the top-level domain name, which is a subdomain of the primary domain name (first-level domain name). For example, in "blog.example.com", "example.com" is the primary domain name (first-level domain name), and "blog" is the second-level domain name.

2. Function

-Website content distinction: Second-level domain names are often used to distinguish different functional modules or content sections in a website. For example, many large e-commerce websites use second-level domain names to distinguish different product categories, such as "clothes.example.com" for displaying clothing products, and "electronics.example.com" for displaying electronic products, which allows users to find the content they want more clearly, and also facilitates the management and maintenance of the website.

3. Creation and Management

-Creation method: Creating a second-level domain name usually requires operation in the control panel provided by the domain name registrar or website hosting service provider. Generally, you need to have the management authority of the primary domain name first, and then create it by adding the function of adding a subdomain name (second-level domain name).

-Management authority: The management authority of the second-level domain name can be assigned by the owner of the primary domain name. The owner can grant the management authority of different second-level domain names to different individuals or teams as needed. For example, website developers can manage technology-related second-level domain names, and marketing personnel can manage marketing-related second-level domain names, which is convenient for division of labor and collaboration.

4. Relationship with other level domain names

-Influence of the upper-level domain name: The operation and resolution of the second-level domain name depend on the configuration of the primary domain name (first-level domain name). The domain name server (DNS) settings of the primary domain name will affect the resolution of the second-level domain name. If there is a problem with the DNS of the primary domain name, the second-level domain name may also not be accessible normally. At the same time, the reputation of the primary domain name (such as its reputation in search engines) will also affect the second-level domain name to a certain extent, but the second-level domain name can also establish an independent reputation through its own high-quality content and good operation.

-Relationship of subordinate domain names: The second-level domain name can be further divided into third-level domain names, fourth-level domain names, etc. For example, based on the second-level domain name "blog.example.com", you can create a third-level domain name such as "tech.blog.example.com" to subdivide the technical articles in the blog. The creation and management of the lower-level domain name is similar to that of the second-level domain name. Both are expanded on the basis of the upper-level domain name to meet more detailed website architecture and content organization needs.