Subdomains are a way of creating separate accounts within your master account, which are accessed as separate URLs. For example, you could set up a “timber” subdomain on your master account “mydomain.com”, which would be accessed as “timber.mydomain.com”.
However, you do not create a new cPanel when you create a subdomain. However you can still perform most administration functions for the subdomain through your master cPanel.
Practically, a subdomain is a sub folder within the public_html level of your account that has it’s own cgi-bin directory. The ‘timber’ example above creates a new top-level folder called ‘timber’. Upload your files for the subdomain to this location, including a separate home file (such as index.htm).
The public and reminder folders above would each have their own home or index pages. These home or index pages will be displayed when the sub-domain URL is entered in a browser.