The term Domain-name is very commonly used in IT sector, it’s simply a name used for identification of a particular website over the internet.
Example, the domain name Microsoft.com represents about a dozen IP addresses. It used in URLs to identify particular Web pages.
It is used in identification of one or more IP addresses. The WordPress.com blog comes with a free address, like example .WordPress .com. You can easily get rid of the .WordPress.com part and use a custom domain name instead, like example.com. Adding a domain is a paid upgrade.
A domain- name provides you with a unique identity..