For Main Domain
All domain names in your account have a document root. The document root is the folder that stores the files for your website. The document root for your main domain name is the public_html folder. When you are ready to upload your website, the files will go into the public_html folder. Once you have uploaded an index page, it will over-ride the default “Hello There!” page that accounts show upon sign-up.
For Addon and Sub Domains
When you add additional domains to your account, it will create a folder in your public_html folder for that domain. With a subdomain the folder will be called the same name as the subdomain, for example public_html/subdomain. For an Addon Domain, by default it will create a folder in your public_html folder with the same name as the Addon Domain. If you would like you can change the document root for your Addon Domain when it is created to a different folder.