A name that identifies a computer or computers on the Internet. These names appear as a component of a Web site’s URL, e.g. en.wikipedia.org. This type of domain name is also called a host-name.
The product that domain name registrars provide to their customers. These names are often called registered domain names.
Names used for other purposes in the Domain Name System (DNS), for example the special name which follows the @ sign in an email address, or the
Top-level domain names like .com, or the names used by the Session Initiation Protocol, or DomainKeys.
They are sometimes colloquially (and incorrectly) referred to by marketers as “web addresses”.