Domains and DNS

A domain name is the name that people type in their browsers to access
your website.

A domain name is hierarchical and can consist of a number of parts
called labels:

• The label furthest to the right is called the top-level domain. For
  example, com is the top-level domain of www.example.com. The
  number of top-level domains is limited and all of them are managed by
  separate international authorities.
• The second-level domain is the label that we mainly use to imply
  the purpose of our website. In www.example.com it is the
  example part. The combination of the second-level and top-level
  domain names specifies the exact location of your website.
• Each label to the left is a subdomain of the domain to the right. For
  example, www is the subdomain of example.com. Subdomains can
  be convenient when you want to isolate some content from the main
  site, e.g. you can organize your personal blog on
  myblog.example.com. For information on how to add subdomains in
  Plesk, refer to the section Adding Subdomains.

If you want to host more than one website under your subscription, you
can register more domains and add them to your subscription. Registering
new domains may be available to you in the Customer Panel if your
hosting provider allows this. For information on how to purchase and add
domains in Plesk, refer to the section Adding Domains.

In fact, domain names exist only for convenience; the real communication
between browser and web servers uses IP addresses - the numerical host
identifiers. For example, the real address of www.example.com may be
192.0.2.12 (IPv4). To resolve domain names into IP addresses, web hosts
use DNS technology. For more details about how DNS is implemented in
Plesk, refer to the section (Advanced) Configuring DNS for a
Domain.

DNS allows several domains to be resolved into one IP address. Such
additional names are called domain aliases. This is convenient when you
have purchased several domains that you want to point to the same
website. For information on how to add aliases to existing domains,
refer to the section Adding Domain Aliases.