Domain pointers are needed to redirect the HTTP requests to the folder within the web server that contains your website/s.
They are needed if you host different websites for different domains. Each website needs to be located in a different folder within /htdocs. Then you need to point each domain and host within this domain (eg. WWW) to a different folder.
For example, if you have 2 domains: domain1.com and domain2.com, you will need to first create the folders within the web server (hosting control panel > FTP & Content Publishing > File Manager), then create the domain pointers this way:
1. Log in to your account and go to PRODUCTS > HOSTING.
2. Move the cursor to the domain name concerned and click on View.
3. Click on Manage.
4. Go to Configurations and click on Domain Pointers.
5. Click on Add.
6. Enter the domain name and select the option Point to a sub-directory. Enter the name of the folder you created for this domain, click on OK.
The domain pointer will be created for the apex domain and for the WWW host in this domain. For example: domain1.com and www.domain1.com.