What is an Addon Domain?
An addon domain is an independent domain name on
your hosting account. It points to its own folder within the public_html, so
it is like another website separate from your primary one.
You can give an addon domain its own email addresses, forwarders, and more, the
same way as you can for the primary (main) domain on your account.
For
example, you can have cars.com as your primary domain and candy.com as
an addon domain, and both domains would have their own separate
websites and functionalities.
You can create addon domain from Domains > Addon Domains in your cPanel.
What is a Parked Domain?
A parked domain is an alias of your primary
domain — it points to your primary domain. The domain is forwarded to the same website.
For example, if cars.com is your main web
site, you can purchase cars.net and assign it as a parked domain. Then,
if a visitor were to go to cars.net, they would see the same website as
if they had typed cars.com.
In other words, both primarydomain.com/index.htm and parkeddomain.com/index.htm will point to the same webpage "index.htm".
You can setup parked domain from Domains > Aliases in your cPanel.
What is a Subdomain?
A subdomain is a prefix added to your original domain name, like a domain within a domain, usually following the form subdomain.example.com. They behave very similar to an addon domain, and are often created to separate different sections of your website, such as blog.example.com or store.example.com.You can create a subdomain from Domains > Subdomains in your cPanel.