Every single registered domain name has a minimum of two Name Server records which show where it is hosted i.e. by using these records you point your domain to the servers of a particular website hosting provider. This way, you have got both your website and your e-mails managed by the very same company. On the lower level of the Domain Name System (DNS), on the other hand, there is a variety of other records, such as A and MX. The former shows which server manages the site for a given Internet domain and is always an IP address (123.123.123.123), while the second one shows which server manages the emails and is always an alphanumeric string (mx1.domain.com). For instance, whenever you type a domain address in your Internet browser, your request is directed through the global DNS system to the provider whose NS records the domain uses and from there you may be directed to the servers of a different service provider if you have set an IP address of the latter as an A record for your domain address. Having different records for the website and the emails suggests that you could have your site and your emails with two different providers if you wish.
