Subdomains are used in web hosting to create separate and distinct sections or branches of a website under the main domain name. They allow you to organize and manage different content, services, or functionalities within your overall web hosting environment. Subdomains are created by adding a prefix to your main domain name and are often used for specific purposes. Here are some common uses of subdomains in web hosting:

1. **Content Organization**: Subdomains are an excellent way to organize and categorize different types of content on your website. For example, you might have a subdomain for your blog, another for your e-commerce store, and another for your support portal. This makes it easier for visitors to navigate to specific sections of your site.

2. **Language or Region Specific Content**: If you offer content in multiple languages or cater to different regions, you can use subdomains to provide localized versions of your site. For example, you might have en.example.com for English content and fr.example.com for French content.

3. **Mobile Version**: You can create a subdomain specifically optimized for mobile devices, providing a responsive or mobile-friendly version of your website.

4. **Testing and Staging**: Subdomains are often used for testing and staging purposes. You can create a subdomain like test.example.com or staging.example.com to develop and test new features or changes before deploying them to the main site.

5. **APIs and Services**: Subdomains can be used to host APIs (Application Programming Interfaces) or other web services that your main website relies on. For instance, api.example.com might serve as the endpoint for your application’s API.

6. **Separate Microsites**: If you have different products or services that you want to promote separately, you can create dedicated microsites as subdomains. For instance, product1.example.com and product2.example.com.

7. **User Profiles or Subscribers**: Subdomains can be used to provide personalized pages for user profiles or subscribers. For example, user1.example.com could lead to a profile page for the user “User1.”

8. **Media or File Hosting**: Subdomains can be used to serve media files like images, videos, or downloadable content, keeping these resources separate from your main website files.

9. **Landing Pages**: Subdomains can be utilized for specific landing pages or campaigns, helping you track and measure the performance of targeted marketing efforts.

10. **Custom Applications**: If you have custom web applications or services, you can create subdomains to host these applications independently from your main website.

Subdomains offer flexibility and organization within your web hosting environment, allowing you to manage different sections or functionalities of your website while maintaining a cohesive overall online presence. They provide a structured way to deliver specific content or services to your audience.