The term comes from the English word 'domain' (ownership, possession). In practice, this is the right of possession of a name for a specified time. Behind each name with a numeric IP address of a particular computer on the Internet. Domain names are unique and can not be repeated.
By registering a domain name and its connection to a site and / or e-mail address the user makes a website and e-mail addresses accessible and visible from any other computer, becoming an integral part of the global network.